linux/arch/powerpc/lib/ldstfp.S

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powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
/*
* Floating-point, VMX/Altivec and VSX loads and stores
* for use in instruction emulation.
*
* Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <asm/processor.h>
#include <asm/ppc_asm.h>
#include <asm/ppc-opcode.h>
#include <asm/reg.h>
#include <asm/asm-offsets.h>
#include <asm/asm-compat.h>
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
#include <linux/errno.h>
#ifdef CONFIG_PPC_FPU
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
#define STKFRM (PPC_MIN_STKFRM + 16)
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
/* Get the contents of frN into *p; N is in r3 and p is in r4. */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
_GLOBAL(get_fpr)
mflr r0
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
mfmsr r6
ori r7, r6, MSR_FP
MTMSRD(r7)
isync
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
rlwinm r3,r3,3,0xf8
bcl 20,31,1f
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
reg = 0
.rept 32
stfd reg, 0(r4)
b 2f
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
reg = reg + 1
.endr
1: mflr r5
add r5,r3,r5
mtctr r5
mtlr r0
bctr
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
2: MTMSRD(r6)
isync
blr
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
/* Put the contents of *p into frN; N is in r3 and p is in r4. */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
_GLOBAL(put_fpr)
mflr r0
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
mfmsr r6
ori r7, r6, MSR_FP
MTMSRD(r7)
isync
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
rlwinm r3,r3,3,0xf8
bcl 20,31,1f
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
reg = 0
.rept 32
lfd reg, 0(r4)
b 2f
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
reg = reg + 1
.endr
1: mflr r5
add r5,r3,r5
mtctr r5
mtlr r0
bctr
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
2: MTMSRD(r6)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
blr
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
#ifdef CONFIG_ALTIVEC
/* Get the contents of vrN into *p; N is in r3 and p is in r4. */
_GLOBAL(get_vr)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
mflr r0
mfmsr r6
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
oris r7, r6, MSR_VEC@h
MTMSRD(r7)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
powerpc: Fix kernel crash in emulation of vector loads and stores Commit 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code", 2017-08-30) changed the register usage in get_vr and put_vr with the aim of leaving the register number in r3 untouched on return. Unfortunately, r6 was not a good choice, as the callers as of 350779a29f11 store a MSR value in r6. Then, in commit c22435a5f3d8 ("powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live", 2017-08-30), the saving and restoring of the MSR got moved into get_vr and put_vr. Either way, the effect is that we put a value in MSR that only has the 0x3f8 bits non-zero, meaning that we are switching to 32-bit mode. That leads to a crash like this: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x0007bea0 Oops: Kernel access of bad area, sig: 11 [#12] LE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G D 4.13.0-rc2-00313-gf3026f57e6ed-dirty #23 task: c000000f1bb9e780 task.stack: c000000f1ba98000 NIP: 000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70 REGS: c000000f1ba9b960 TRAP: 0400 Tainted: G D (4.13.0-rc2-00313-gf3026f57e6ed-dirty) MSR: 10000000400010a1 <HV,ME,IR,LE> CR: 48000228 XER: 00000000 CFAR: c00000000007be74 SOFTE: 1 GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033 GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009 GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5 GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000 GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000 GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001 GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001 NIP [000000000007bea0] 0x7bea0 LR [c00000000007b054] emulate_loadstore+0x1044/0x1280 Call Trace: [c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable) [c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544 [c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40 [c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0 [c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0 [c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace a7ae7a7f3e0256b5 ]--- To fix this, we just revert to using r3 as before, since the callers don't rely on r3 being left unmodified. Fortunately, this can't be triggered by a misaligned load or store, because vector loads and stores truncate misaligned addresses rather than taking an alignment interrupt. It can be triggered using uprobes. Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Reported-by: Anton Blanchard <anton@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-04 11:59:00 +08:00
rlwinm r3,r3,3,0xf8
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
bcl 20,31,1f
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
reg = 0
.rept 32
stvx reg, 0, r4
b 2f
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
reg = reg + 1
.endr
1: mflr r5
powerpc: Fix kernel crash in emulation of vector loads and stores Commit 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code", 2017-08-30) changed the register usage in get_vr and put_vr with the aim of leaving the register number in r3 untouched on return. Unfortunately, r6 was not a good choice, as the callers as of 350779a29f11 store a MSR value in r6. Then, in commit c22435a5f3d8 ("powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live", 2017-08-30), the saving and restoring of the MSR got moved into get_vr and put_vr. Either way, the effect is that we put a value in MSR that only has the 0x3f8 bits non-zero, meaning that we are switching to 32-bit mode. That leads to a crash like this: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x0007bea0 Oops: Kernel access of bad area, sig: 11 [#12] LE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G D 4.13.0-rc2-00313-gf3026f57e6ed-dirty #23 task: c000000f1bb9e780 task.stack: c000000f1ba98000 NIP: 000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70 REGS: c000000f1ba9b960 TRAP: 0400 Tainted: G D (4.13.0-rc2-00313-gf3026f57e6ed-dirty) MSR: 10000000400010a1 <HV,ME,IR,LE> CR: 48000228 XER: 00000000 CFAR: c00000000007be74 SOFTE: 1 GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033 GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009 GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5 GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000 GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000 GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001 GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001 NIP [000000000007bea0] 0x7bea0 LR [c00000000007b054] emulate_loadstore+0x1044/0x1280 Call Trace: [c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable) [c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544 [c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40 [c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0 [c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0 [c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace a7ae7a7f3e0256b5 ]--- To fix this, we just revert to using r3 as before, since the callers don't rely on r3 being left unmodified. Fortunately, this can't be triggered by a misaligned load or store, because vector loads and stores truncate misaligned addresses rather than taking an alignment interrupt. It can be triggered using uprobes. Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Reported-by: Anton Blanchard <anton@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-04 11:59:00 +08:00
add r5,r3,r5
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
mtctr r5
mtlr r0
bctr
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
2: MTMSRD(r6)
isync
blr
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
/* Put the contents of *p into vrN; N is in r3 and p is in r4. */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
_GLOBAL(put_vr)
mflr r0
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
mfmsr r6
oris r7, r6, MSR_VEC@h
MTMSRD(r7)
isync
powerpc: Fix kernel crash in emulation of vector loads and stores Commit 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code", 2017-08-30) changed the register usage in get_vr and put_vr with the aim of leaving the register number in r3 untouched on return. Unfortunately, r6 was not a good choice, as the callers as of 350779a29f11 store a MSR value in r6. Then, in commit c22435a5f3d8 ("powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live", 2017-08-30), the saving and restoring of the MSR got moved into get_vr and put_vr. Either way, the effect is that we put a value in MSR that only has the 0x3f8 bits non-zero, meaning that we are switching to 32-bit mode. That leads to a crash like this: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x0007bea0 Oops: Kernel access of bad area, sig: 11 [#12] LE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G D 4.13.0-rc2-00313-gf3026f57e6ed-dirty #23 task: c000000f1bb9e780 task.stack: c000000f1ba98000 NIP: 000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70 REGS: c000000f1ba9b960 TRAP: 0400 Tainted: G D (4.13.0-rc2-00313-gf3026f57e6ed-dirty) MSR: 10000000400010a1 <HV,ME,IR,LE> CR: 48000228 XER: 00000000 CFAR: c00000000007be74 SOFTE: 1 GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033 GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009 GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5 GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000 GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000 GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001 GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001 NIP [000000000007bea0] 0x7bea0 LR [c00000000007b054] emulate_loadstore+0x1044/0x1280 Call Trace: [c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable) [c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544 [c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40 [c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0 [c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0 [c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace a7ae7a7f3e0256b5 ]--- To fix this, we just revert to using r3 as before, since the callers don't rely on r3 being left unmodified. Fortunately, this can't be triggered by a misaligned load or store, because vector loads and stores truncate misaligned addresses rather than taking an alignment interrupt. It can be triggered using uprobes. Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Reported-by: Anton Blanchard <anton@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-04 11:59:00 +08:00
rlwinm r3,r3,3,0xf8
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
bcl 20,31,1f
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
reg = 0
.rept 32
lvx reg, 0, r4
b 2f
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
reg = reg + 1
.endr
1: mflr r5
powerpc: Fix kernel crash in emulation of vector loads and stores Commit 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code", 2017-08-30) changed the register usage in get_vr and put_vr with the aim of leaving the register number in r3 untouched on return. Unfortunately, r6 was not a good choice, as the callers as of 350779a29f11 store a MSR value in r6. Then, in commit c22435a5f3d8 ("powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live", 2017-08-30), the saving and restoring of the MSR got moved into get_vr and put_vr. Either way, the effect is that we put a value in MSR that only has the 0x3f8 bits non-zero, meaning that we are switching to 32-bit mode. That leads to a crash like this: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x0007bea0 Oops: Kernel access of bad area, sig: 11 [#12] LE SMP NR_CPUS=2048 NUMA PowerNV Modules linked in: vmx_crypto binfmt_misc ip_tables x_tables autofs4 crc32c_vpmsum CPU: 6 PID: 32659 Comm: trashy_testcase Tainted: G D 4.13.0-rc2-00313-gf3026f57e6ed-dirty #23 task: c000000f1bb9e780 task.stack: c000000f1ba98000 NIP: 000000000007bea0 LR: c00000000007b054 CTR: c00000000007be70 REGS: c000000f1ba9b960 TRAP: 0400 Tainted: G D (4.13.0-rc2-00313-gf3026f57e6ed-dirty) MSR: 10000000400010a1 <HV,ME,IR,LE> CR: 48000228 XER: 00000000 CFAR: c00000000007be74 SOFTE: 1 GPR00: c00000000007b054 c000000f1ba9bbe0 c000000000e6e000 000000000000001d GPR04: c000000f1ba9bc00 c00000000007be70 00000000000000e8 9000000002009033 GPR08: 0000000002000000 100000000282f033 000000000b0a0900 0000000000001009 GPR12: 0000000000000000 c00000000fd42100 0706050303020100 a5a5a5a5a5a5a5a5 GPR16: 2e2e2e2e2e2de70c 2e2e2e2e2e2e2e2d 0000000000ff00ff 0606040202020000 GPR20: 000000000000005b ffffffffffffffff 0000000003020100 0000000000000000 GPR24: c000000f1ab90020 c000000f1ba9bc00 0000000000000001 0000000000000001 GPR28: c000000f1ba9bc90 c000000f1ba9bea0 000000000b0a0908 0000000000000001 NIP [000000000007bea0] 0x7bea0 LR [c00000000007b054] emulate_loadstore+0x1044/0x1280 Call Trace: [c000000f1ba9bbe0] [c000000000076b80] analyse_instr+0x60/0x34f0 (unreliable) [c000000f1ba9bc70] [c00000000007b7ec] emulate_step+0x23c/0x544 [c000000f1ba9bce0] [c000000000053424] arch_uprobe_skip_sstep+0x24/0x40 [c000000f1ba9bd00] [c00000000024b2f8] uprobe_notify_resume+0x598/0xba0 [c000000f1ba9be00] [c00000000001c284] do_notify_resume+0xd4/0xf0 [c000000f1ba9be30] [c00000000000bd44] ret_from_except_lite+0x70/0x74 Instruction dump: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX ---[ end trace a7ae7a7f3e0256b5 ]--- To fix this, we just revert to using r3 as before, since the callers don't rely on r3 being left unmodified. Fortunately, this can't be triggered by a misaligned load or store, because vector loads and stores truncate misaligned addresses rather than taking an alignment interrupt. It can be triggered using uprobes. Fixes: 350779a29f11 ("powerpc: Handle most loads and stores in instruction emulation code") Reported-by: Anton Blanchard <anton@ozlabs.org> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Tested-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-09-04 11:59:00 +08:00
add r5,r3,r5
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
mtctr r5
mtlr r0
bctr
powerpc: Emulate FP/vector/VSX loads/stores correctly when regs not live At present, the analyse_instr/emulate_step code checks for the relevant MSR_FP/VEC/VSX bit being set when a FP/VMX/VSX load or store is decoded, but doesn't recheck the bit before reading or writing the relevant FP/VMX/VSX register in emulate_step(). Since we don't have preemption disabled, it is possible that we get preempted between checking the MSR bit and doing the register access. If that happened, then the registers would have been saved to the thread_struct for the current process. Accesses to the CPU registers would then potentially read stale values, or write values that would never be seen by the user process. Another way that the registers can become non-live is if a page fault occurs when accessing user memory, and the page fault code calls a copy routine that wants to use the VMX or VSX registers. To fix this, the code for all the FP/VMX/VSX loads gets restructured so that it forms an image in a local variable of the desired register contents, then disables preemption, checks the MSR bit and either sets the CPU register or writes the value to the thread struct. Similarly, the code for stores checks the MSR bit, copies either the CPU register or the thread struct to a local variable, then reenables preemption and then copies the register image to memory. If the instruction being emulated is in the kernel, then we must not use the register values in the thread_struct. In this case, if the relevant MSR enable bit is not set, then emulate_step refuses to emulate the instruction. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-30 12:12:33 +08:00
2: MTMSRD(r6)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
blr
#endif /* CONFIG_ALTIVEC */
#ifdef CONFIG_VSX
/* Get the contents of vsN into vs0; N is in r3. */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
_GLOBAL(get_vsr)
mflr r0
rlwinm r3,r3,3,0x1f8
bcl 20,31,1f
blr /* vs0 is already in vs0 */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
nop
reg = 1
.rept 63
XXLOR(0,reg,reg)
blr
reg = reg + 1
.endr
1: mflr r5
add r5,r3,r5
mtctr r5
mtlr r0
bctr
/* Put the contents of vs0 into vsN; N is in r3. */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
_GLOBAL(put_vsr)
mflr r0
rlwinm r3,r3,3,0x1f8
bcl 20,31,1f
blr /* v0 is already in v0 */
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
nop
reg = 1
.rept 63
XXLOR(reg,0,0)
blr
reg = reg + 1
.endr
1: mflr r5
add r5,r3,r5
mtctr r5
mtlr r0
bctr
/* Load VSX reg N from vector doubleword *p. N is in r3, p in r4. */
_GLOBAL(load_vsrn)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
PPC_STLU r1,-STKFRM(r1)
mflr r0
PPC_STL r0,STKFRM+PPC_LR_STKOFF(r1)
mfmsr r6
oris r7,r6,MSR_VSX@h
cmpwi cr7,r3,0
li r8,STKFRM-16
MTMSRD(r7)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
beq cr7,1f
STXVD2X(0,R1,R8)
1: LXVD2X(0,R0,R4)
#ifdef __LITTLE_ENDIAN__
XXSWAPD(0,0)
#endif
beq cr7,4f
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
bl put_vsr
LXVD2X(0,R1,R8)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
4: PPC_LL r0,STKFRM+PPC_LR_STKOFF(r1)
mtlr r0
MTMSRD(r6)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
addi r1,r1,STKFRM
blr
/* Store VSX reg N to vector doubleword *p. N is in r3, p in r4. */
_GLOBAL(store_vsrn)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
PPC_STLU r1,-STKFRM(r1)
mflr r0
PPC_STL r0,STKFRM+PPC_LR_STKOFF(r1)
mfmsr r6
oris r7,r6,MSR_VSX@h
li r8,STKFRM-16
MTMSRD(r7)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
STXVD2X(0,R1,R8)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
bl get_vsr
#ifdef __LITTLE_ENDIAN__
XXSWAPD(0,0)
#endif
STXVD2X(0,R0,R4)
LXVD2X(0,R1,R8)
PPC_LL r0,STKFRM+PPC_LR_STKOFF(r1)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
mtlr r0
MTMSRD(r6)
powerpc: Emulate most Book I instructions in emulate_step() This extends the emulate_step() function to handle a large proportion of the Book I instructions implemented on current 64-bit server processors. The aim is to handle all the load and store instructions used in the kernel, plus all of the instructions that appear between l[wd]arx and st[wd]cx., so this handles the Altivec/VMX lvx and stvx and the VSX lxv2dx and stxv2dx instructions (implemented in POWER7). The new code can emulate user mode instructions, and checks the effective address for a load or store if the saved state is for user mode. It doesn't handle little-endian mode at present. For floating-point, Altivec/VMX and VSX instructions, it checks that the saved MSR has the enable bit for the relevant facility set, and if so, assumes that the FP/VMX/VSX registers contain valid state, and does loads or stores directly to/from the FP/VMX/VSX registers, using assembly helpers in ldstfp.S. Instructions supported now include: * Loads and stores, including some but not all VMX and VSX instructions, and lmw/stmw * Atomic loads and stores (l[dw]arx, st[dw]cx.) * Arithmetic instructions (add, subtract, multiply, divide, etc.) * Compare instructions * Rotate and mask instructions * Shift instructions * Logical instructions (and, or, xor, etc.) * Condition register logical instructions * mtcrf, cntlz[wd], exts[bhw] * isync, sync, lwsync, ptesync, eieio * Cache operations (dcbf, dcbst, dcbt, dcbtst) The overflow-checking arithmetic instructions are not included, but they appear not to be ever used in C code. This uses decimal values for the minor opcodes in the switch statements because that is what appears in the Power ISA specification, thus it is easier to check that they are correct if they are in decimal. If this is used to single-step an instruction where a data breakpoint interrupt occurred, then there is the possibility that the instruction is a lwarx or ldarx. In that case we have to be careful not to lose the reservation until we get to the matching st[wd]cx., or we'll never make forward progress. One alternative is to try to arrange that we can return from interrupts and handle data breakpoint interrupts without losing the reservation, which means not using any spinlocks, mutexes, or atomic ops (including bitops). That seems rather fragile. The other alternative is to emulate the larx/stcx and all the instructions in between. This is why this commit adds support for a wide range of integer instructions. Signed-off-by: Paul Mackerras <paulus@samba.org>
2010-06-15 12:48:58 +08:00
isync
mr r3,r9
addi r1,r1,STKFRM
blr
#endif /* CONFIG_VSX */
/* Convert single-precision to double, without disturbing FPRs. */
/* conv_sp_to_dp(float *sp, double *dp) */
_GLOBAL(conv_sp_to_dp)
mfmsr r6
ori r7, r6, MSR_FP
MTMSRD(r7)
isync
stfd fr0, -16(r1)
lfs fr0, 0(r3)
stfd fr0, 0(r4)
lfd fr0, -16(r1)
MTMSRD(r6)
isync
blr
/* Convert single-precision to double, without disturbing FPRs. */
/* conv_sp_to_dp(double *dp, float *sp) */
_GLOBAL(conv_dp_to_sp)
mfmsr r6
ori r7, r6, MSR_FP
MTMSRD(r7)
isync
stfd fr0, -16(r1)
lfd fr0, 0(r3)
stfs fr0, 0(r4)
lfd fr0, -16(r1)
MTMSRD(r6)
isync
blr
#endif /* CONFIG_PPC_FPU */