From 5e63215c2f64079fbd011df5005c8bea63f149c2 Mon Sep 17 00:00:00 2001 From: Vitaly Wool Date: Mon, 31 May 2021 11:53:42 +0300 Subject: [PATCH 1/4] riscv: xip: support runtime trap patching RISCV_ERRATA_ALTERNATIVE patches text at runtime which is currently not possible when the kernel is executed from the flash in XIP mode. Since runtime patching concerns only traps at the moment, let's just have all the traps reside in RAM anyway if RISCV_ERRATA_ALTERNATIVE is set. Thus, these functions will be patch-able even when the .text section is in flash. Signed-off-by: Vitaly Wool Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/traps.c | 13 +++++++++---- arch/riscv/kernel/vmlinux-xip.lds.S | 15 ++++++++++++++- 2 files changed, 23 insertions(+), 5 deletions(-) diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 0721b9798595..7bc88d8aab97 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -86,8 +86,13 @@ static void do_trap_error(struct pt_regs *regs, int signo, int code, } } +#if defined (CONFIG_XIP_KERNEL) && defined (CONFIG_RISCV_ERRATA_ALTERNATIVE) +#define __trap_section __section(".xip.traps") +#else +#define __trap_section +#endif #define DO_ERROR_INFO(name, signo, code, str) \ -asmlinkage __visible void name(struct pt_regs *regs) \ +asmlinkage __visible __trap_section void name(struct pt_regs *regs) \ { \ do_trap_error(regs, signo, code, regs->epc, "Oops - " str); \ } @@ -111,7 +116,7 @@ DO_ERROR_INFO(do_trap_store_misaligned, int handle_misaligned_load(struct pt_regs *regs); int handle_misaligned_store(struct pt_regs *regs); -asmlinkage void do_trap_load_misaligned(struct pt_regs *regs) +asmlinkage void __trap_section do_trap_load_misaligned(struct pt_regs *regs) { if (!handle_misaligned_load(regs)) return; @@ -119,7 +124,7 @@ asmlinkage void do_trap_load_misaligned(struct pt_regs *regs) "Oops - load address misaligned"); } -asmlinkage void do_trap_store_misaligned(struct pt_regs *regs) +asmlinkage void __trap_section do_trap_store_misaligned(struct pt_regs *regs) { if (!handle_misaligned_store(regs)) return; @@ -146,7 +151,7 @@ static inline unsigned long get_break_insn_length(unsigned long pc) return GET_INSN_LENGTH(insn); } -asmlinkage __visible void do_trap_break(struct pt_regs *regs) +asmlinkage __visible __trap_section void do_trap_break(struct pt_regs *regs) { #ifdef CONFIG_KPROBES if (kprobe_single_step_handler(regs)) diff --git a/arch/riscv/kernel/vmlinux-xip.lds.S b/arch/riscv/kernel/vmlinux-xip.lds.S index 4b29b9917f99..a3ff09c4c3f9 100644 --- a/arch/riscv/kernel/vmlinux-xip.lds.S +++ b/arch/riscv/kernel/vmlinux-xip.lds.S @@ -99,9 +99,22 @@ SECTIONS } PERCPU_SECTION(L1_CACHE_BYTES) - . = ALIGN(PAGE_SIZE); + . = ALIGN(8); + .alternative : { + __alt_start = .; + *(.alternative) + __alt_end = .; + } __init_end = .; + . = ALIGN(16); + .xip.traps : { + __xip_traps_start = .; + *(.xip.traps) + __xip_traps_end = .; + } + + . = ALIGN(PAGE_SIZE); .sdata : { __global_pointer$ = . + 0x800; *(.sdata*) From 42e0e0b453bc6ead49c573ed512502069627546b Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Tue, 11 May 2021 00:28:38 +0800 Subject: [PATCH 2/4] riscv: code patching only works on !XIP_KERNEL Some features which need code patching such as KPROBES, DYNAMIC_FTRACE KGDB can only work on !XIP_KERNEL. Add dependencies for these features that rely on code patching. Signed-off-by: Jisheng Zhang Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index c5914e70a0fd..18ec0f9bb8d5 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -61,11 +61,11 @@ config RISCV select GENERIC_TIME_VSYSCALL if MMU && 64BIT select HANDLE_DOMAIN_IRQ select HAVE_ARCH_AUDITSYSCALL - select HAVE_ARCH_JUMP_LABEL - select HAVE_ARCH_JUMP_LABEL_RELATIVE + select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL + select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL select HAVE_ARCH_KASAN if MMU && 64BIT select HAVE_ARCH_KASAN_VMALLOC if MMU && 64BIT - select HAVE_ARCH_KGDB + select HAVE_ARCH_KGDB if !XIP_KERNEL select HAVE_ARCH_KGDB_QXFER_PKT select HAVE_ARCH_MMAP_RND_BITS if MMU select HAVE_ARCH_SECCOMP_FILTER @@ -80,9 +80,9 @@ config RISCV select HAVE_GCC_PLUGINS select HAVE_GENERIC_VDSO if MMU && 64BIT select HAVE_IRQ_TIME_ACCOUNTING - select HAVE_KPROBES - select HAVE_KPROBES_ON_FTRACE - select HAVE_KRETPROBES + select HAVE_KPROBES if !XIP_KERNEL + select HAVE_KPROBES_ON_FTRACE if !XIP_KERNEL + select HAVE_KRETPROBES if !XIP_KERNEL select HAVE_PCI select HAVE_PERF_EVENTS select HAVE_PERF_REGS @@ -231,11 +231,11 @@ config ARCH_RV64I bool "RV64I" select 64BIT select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && GCC_VERSION >= 50000 - select HAVE_DYNAMIC_FTRACE if MMU && $(cc-option,-fpatchable-function-entry=8) + select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8) select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE - select HAVE_FTRACE_MCOUNT_RECORD + select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER - select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_TRACER if !XIP_KERNEL select SWIOTLB if MMU endchoice From 858cf860494fab545abfa206d17efcb8bee73e36 Mon Sep 17 00:00:00 2001 From: Vitaly Wool Date: Mon, 31 May 2021 12:33:10 +0300 Subject: [PATCH 3/4] riscv: alternative: fix typo in macro name alternative-macros.h defines ALT_NEW_CONTENT in its assembly part and ALT_NEW_CONSTENT in the C part. Most likely it is the latter that is wrong. Fixes: 6f4eea90465ad (riscv: Introduce alternative mechanism to apply errata solution) Signed-off-by: Vitaly Wool Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/alternative-macros.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/riscv/include/asm/alternative-macros.h b/arch/riscv/include/asm/alternative-macros.h index 88c08705f64a..67406c376389 100644 --- a/arch/riscv/include/asm/alternative-macros.h +++ b/arch/riscv/include/asm/alternative-macros.h @@ -51,7 +51,7 @@ REG_ASM " " newlen "\n" \ ".word " errata_id "\n" -#define ALT_NEW_CONSTENT(vendor_id, errata_id, enable, new_c) \ +#define ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) \ ".if " __stringify(enable) " == 1\n" \ ".pushsection .alternative, \"a\"\n" \ ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(errata_id), "889f - 888f") \ @@ -69,7 +69,7 @@ "886 :\n" \ old_c "\n" \ "887 :\n" \ - ALT_NEW_CONSTENT(vendor_id, errata_id, enable, new_c) + ALT_NEW_CONTENT(vendor_id, errata_id, enable, new_c) #define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, CONFIG_k) \ __ALTERNATIVE_CFG(old_c, new_c, vendor_id, errata_id, IS_ENABLED(CONFIG_k)) From 0ddd7eaffa644baa78e247bbd220ab7195b1eed6 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Fri, 4 Jun 2021 14:06:39 +0200 Subject: [PATCH 4/4] riscv: Fix BUILTIN_DTB for sifive and microchip soc Fix BUILTIN_DTB config which resulted in a dtb that was actually not built into the Linux image: in the same manner as Canaan soc does, create an object file from the dtb file that will get linked into the Linux image. Signed-off-by: Alexandre Ghiti Signed-off-by: Palmer Dabbelt --- arch/riscv/boot/dts/microchip/Makefile | 1 + arch/riscv/boot/dts/sifive/Makefile | 1 + 2 files changed, 2 insertions(+) diff --git a/arch/riscv/boot/dts/microchip/Makefile b/arch/riscv/boot/dts/microchip/Makefile index 622b12771fd3..855c1502d912 100644 --- a/arch/riscv/boot/dts/microchip/Makefile +++ b/arch/riscv/boot/dts/microchip/Makefile @@ -1,2 +1,3 @@ # SPDX-License-Identifier: GPL-2.0 dtb-$(CONFIG_SOC_MICROCHIP_POLARFIRE) += microchip-mpfs-icicle-kit.dtb +obj-$(CONFIG_BUILTIN_DTB) += $(addsuffix .o, $(dtb-y)) diff --git a/arch/riscv/boot/dts/sifive/Makefile b/arch/riscv/boot/dts/sifive/Makefile index 74c47fe9fc22..d90e4eb0ade8 100644 --- a/arch/riscv/boot/dts/sifive/Makefile +++ b/arch/riscv/boot/dts/sifive/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 dtb-$(CONFIG_SOC_SIFIVE) += hifive-unleashed-a00.dtb \ hifive-unmatched-a00.dtb +obj-$(CONFIG_BUILTIN_DTB) += $(addsuffix .o, $(dtb-y))