Commit Graph

54 Commits

Author SHA1 Message Date
Max Filippov 60deebe614 xtensa: simplify trap_init
Drop redundant 'fast &&' condition from the exception handler assignment
loop.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2019-02-07 12:35:32 -08:00
Max Filippov cad6fade6e xtensa: clean up WSR*/RSR*/get_sr/set_sr
WSR and RSR are too generic and collide with other macro definitions in
the kernel causing warnings in allmodconfig builds. Drop WSR and RSR
macros and WSR_* and RSR_* variants. Change get_sr and set_sr to
xtensa_get_sr and xtensa_set_sr. Fix up users.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-12-04 14:08:11 -08:00
Max Filippov 8ed3a5426b xtensa: drop fast_syscall_kernel
There must be no xtensa-specific syscalls from the kernel code: register
spilling uses call+entry sequence and atomics have proper function
implementations. Drop fast_syscall_xtensa.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2018-12-03 01:39:22 -08:00
Eric W. Biederman 9181010565 signal/xtensa: Use force_sig_fault where appropriate
Filling in struct siginfo before calling force_sig_info a tedious and
error prone process, where once in a great while the wrong fields
are filled out, and siginfo has been inconsistently cleared.

Simplify this process by using the helper force_sig_fault.  Which
takes as a parameters all of the information it needs, ensures
all of the fiddly bits of filling in struct siginfo are done properly
and then calls force_sig_info.

In short about a 5 line reduction in code for every time force_sig_info
is called, which makes the calling function clearer.

Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: linux-xtensa@linux-xtensa.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:44:12 -05:00
Eric W. Biederman 7de712ccc0 signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
While working on changing this code to use force_sig_fault I
discovered that do_unaliged_user is sets si_signo to SIGBUS and passes
SIGSEGV to force_sig_info.  Which is just b0rked.

The code is reporting a SIGBUS error so replace the SIGSEGV with SIGBUS.

Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: linux-xtensa@linux-xtensa.org
Cc: stable@vger.kernel.org
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Fixes: 5a0015d626 ("[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 3")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:44:11 -05:00
Eric W. Biederman 3eb0f5193b signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:40:51 -05:00
Max Filippov f21a79cab3 xtensa: clean up exception handling structure
Instead of using flat array of longs use normal C structure and generate
EXC_TABLE_* constants in the asm-offsets.c

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-12-16 22:37:09 -08:00
Max Filippov c130d3be84 xtensa: clean up custom-controlled debug output
Replace #ifdef'fed/commented out debug printk statements with pr_debug.
Replace printk statements with pr_* equivalents.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-12-16 22:37:08 -08:00
Max Filippov e640cc3063 xtensa: fix stack dump output
Use %pB in pr_cont format string instead of calling print_symbol
separately. It turns

  [   19.166249] Call Trace:
  [   19.167265]  [<a000e50a>]
  [   19.167843]  __warn+0x92/0xa0
  [   19.169656]  [<a000e554>]
  [   19.170059]  warn_slowpath_fmt+0x3c/0x40
  [   19.171934]  [<a02d5bd8>]

back into

  [   18.123240] Call Trace:
  [   18.125039]  [<a000e4f6>] __warn+0x92/0xa0
  [   18.126961]  [<a000e540>] warn_slowpath_fmt+0x3c/0x40

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2017-03-31 15:58:40 -07:00
Ingo Molnar 3f8c24529b sched/headers: Prepare to move kstack_end() from <linux/sched.h> to <linux/sched/task_stack.h>
But first update the usage sites with the new header dependency.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:39 +01:00
Ingo Molnar b17b01533b sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:34 +01:00
Ingo Molnar 3f07c01441 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/signal.h>
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:29 +01:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Max Filippov d4eccafcaf xtensa: clean up printk usage for boot/crash logging
Convert printk(KERN_* to pr_* and printk's without level to pr_cont.
This fixes torn register dumps, stack dumps, stack traces and timestamps
in the middle of 'Calibrating CPU frequency' message.
Also drop unused show_code and drop false comment about show_stack.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-11-06 23:31:46 -08:00
Max Filippov c91e02bd97 xtensa: support hardware breakpoints/watchpoints
Use perf framework to manage hardware instruction and data breakpoints.
Add two new ptrace calls: PTRACE_GETHBPREGS and PTRACE_SETHBPREGS to
query and set instruction and data breakpoints.
Address bit 0 choose instruction (0) or data (1) break register, bits
31..1 are the register number.
Both calls transfer two 32-bit words: address (0) and control (1).
Instruction breakpoint contorl word is 0 to clear breakpoint, 1 to set.
Data breakpoint control word bit 31 is 'trigger on store', bit 30 is
'trigger on load, bits 29..0 are length. Length 0 is used to clear a
breakpoint. To set a breakpoint length must be a power of 2 in the range
1..64 and the address must be length-aligned.

Introduce new thread_info flag: TIF_DB_DISABLED. Set it if debug
exception is raised by the kernel code accessing watched userspace
address and disable corresponding data breakpoint. On exit to userspace
check that flag and, if set, restore all data breakpoints.

Handle debug exceptions raised with PS.EXCM set. This may happen when
window overflow/underflow handler or fast exception handler hits data
breakpoint, in which case save and disable all data breakpoints,
single-step faulting instruction and restore data breakpoints.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11 08:53:32 +00:00
Max Filippov 6ec7026ac0 xtensa: use context structure for debug exceptions
With implementation of data breakpoints debug exceptions raised when
PS.EXCM is set need to be handled, e.g. window overflow code can write
to watched userspace address. Currently debug exception handler uses
EXCSAVE and DEPC SRs to save temporary registers, but DEPC may not be
available when PS.EXCM is set and more space will be needed to save
additional state.
Reorganize debug context: create per-CPU structure debug_table instance
and store its address in the EXCSAVE<debug level> instead of
debug_exception function address. Expand this structure when more save
space is needed.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11 08:53:32 +00:00
Max Filippov 816aa58895 xtensa: remove remaining non-functional KGDB bits
KGDB is not supported on xtensa, but there are bits of related code
under arch/xtensa/kernel. Remove these bits.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-03-11 08:53:32 +00:00
Max Filippov e462919413 xtensa: make fake NMI configurable
Do not always use fake NMI when safe, provide Kconfig option instead.
Print a warning if fake NMI is chosen in unsafe configuration, but allow
it, because it may work if the user knows that interrupts with
priorities at or above PMM IRQ are not used. Add a check to NMI handler
that BUGs if any of these IRQs fire.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2016-01-11 17:31:55 +03:00
Max Filippov 38fef73c21 xtensa: implement fake NMI
In case perf IRQ is the highest of the medium-level IRQs, and is alone
on its level, it may be treated as NMI:
- LOCKLEVEL is defined to be one level less than EXCM level,
- IRQ masking never lowers current IRQ level,
- new fake exception cause code, EXCCAUSE_MAPPED_NMI is assigned to that
  IRQ; new second level exception handler, do_nmi, assigned to it
  handles it as NMI,
- atomic operations in configurations without s32c1i still need to mask
  all interrupts.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2015-08-17 07:33:39 +03:00
Max Filippov 7d5f6a9a24 xtensa: reorganize irq flags tracing
entry.s only disables IRQs on hardware IRQ, move trace_hardirqs_off call
into do_interrupt. Check actual intlevel that will be restored on return
from exception handler to decide if trace_hardirqs_on should be called.
Annotate IRQ on/off points in the TIF_* handling loop on return from
exception handler.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2015-08-17 07:33:34 +03:00
Max Filippov 3cfc096e4c xtensa: don't allow overflow/underflow on unaligned stack
Double exceptions that happen during register window overflow/underflow
are handled in the topmost stack frame, as if it was the only exception
that occured. However unaligned access exception handler is special
because it needs to analyze instruction that caused the exception, but
the userspace instruction that triggered window exception is completely
irrelevant. Unaligned data access is rather normal in the generic
userspace code, but stack pointer manipulation must always be done by
architecture-aware code and thus unaligned stack means a serious problem
anyway.
Use the default unaligned access handler that raises SIGBUS in case
of unaligned access in window overflow/underflow handler.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
2014-08-14 11:59:32 +04:00
Max Filippov 49b424feda xtensa: implement CPU hotplug
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2014-01-14 10:19:59 -08:00
Max Filippov f615136c06 xtensa: add SMP support
This is largely based on SMP code from the xtensa-2.6.29-smp tree by
Piet Delaney, Marc Gauthier, Joe Taylor, Christian Zankel (and possibly
other Tensilica folks).

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2014-01-14 10:19:58 -08:00
Max Filippov 996232393b xtensa: clean up do_interrupt/do_IRQ
- set up irq registers and call irq_enter/irq_exit once for each kernel
  entry due to interrupt;
- don't attempt to clear current IRQ in the do_interrupt, IRQ handler
  will take care of it;
- find pending interrupt with highest priority before every ISR
  invocation.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2014-01-14 10:19:57 -08:00
Linus Torvalds c61c48dfe0 Xtensa patchset for v3.10-rc1
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Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux

Pull xtensa updates from Chris Zankel:
 "Support for the latest MMU architecture that allows for a larger
  accessible memory region, and various bug-fixes"

* tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux:
  xtensa: Switch to asm-generic/linkage.h
  xtensa: fix redboot load address
  xtensa: ISS: fix timer_lock usage in rs_open
  xtensa: disable IRQs while IRQ handler is running
  xtensa: enable lockdep support
  xtensa: fix arch_irqs_disabled_flags implementation
  xtensa: add irq flags trace support
  xtensa: provide custom CALLER_ADDR* implementations
  xtensa: add stacktrace support
  xtensa: clean up stpill_registers
  xtensa: don't use a7 in simcalls
  xtensa: don't attempt to use unconfigured timers
  xtensa: provide default platform_pcibios_init implementation
  xtensa: remove KCORE_ELF again
  xtensa: document MMUv3 setup sequence
  xtensa: add MMU v3 support
  xtensa: fix ibreakenable register update
  xtensa: fix oprofile building as module
2013-05-09 14:38:16 -07:00
Max Filippov 895666a992 xtensa: disable IRQs while IRQ handler is running
IRQ handlers are expected to run with IRQs disabled.
See e.g. http://lwn.net/Articles/380931/ for a longer story.

This was overlooked in the commit
  2d1c645 xtensa: dispatch medium-priority interrupts
Revert to old behavior and simplify interrupt entry and exit code.
Interrupt handler still honours IRQ priority.

do_notify_resume/schedule must be called with interrupts enabled, enable
interrupts if we return from user exception.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2013-05-09 01:07:11 -07:00
Max Filippov 3e4196a5cc xtensa: add stacktrace support
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2013-05-09 01:07:10 -07:00
Tejun Heo a43cb95d54 dump_stack: unify debug information printed by show_regs()
show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms.  This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.

show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.

* Archs which didn't print debug info now do.

  alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
  metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
  um, xtensa

* Already prints debug info.  Replaced with show_regs_print_info().
  The printed information is superset of what used to be there.

  arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86

* s390 is special in that it used to print arch-specific information
  along with generic debug info.  Heiko and Martin think that the
  arch-specific extra isn't worth keeping s390 specfic implementation.
  Converted to use the generic version.

Note that now all archs print the debug info before actual register
dumps.

An example BUG() dump follows.

 kernel BUG at /work/os/work/kernel/workqueue.c:4841!
 invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
 Hardware name: empty empty/S3992, BIOS 080011  10/26/2007
 task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
 RIP: 0010:[<ffffffff8234a07e>]  [<ffffffff8234a07e>] init_workqueues+0x4/0x6
 RSP: 0000:ffff88007c861ec8  EFLAGS: 00010246
 RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
 RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
 RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
 Stack:
  ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
  0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
  ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
 Call Trace:
  [<ffffffff81000312>] do_one_initcall+0x122/0x170
  [<ffffffff82335e5d>] kernel_init_freeable+0x9b/0x1c8
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  [<ffffffff81c4776e>] kernel_init+0xe/0xf0
  [<ffffffff81c6be9c>] ret_from_fork+0x7c/0xb0
  [<ffffffff81c47760>] ? rest_init+0x140/0x140
  ...

v2: Typo fix in x86-32.

v3: CPU number dropped from show_regs_print_info() as
    dump_stack_print_info() has been updated to print it.  s390
    specific implementation dropped as requested by s390 maintainers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>		[tile bits]
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:02 -07:00
Tejun Heo 196779b9b4 dump_stack: consolidate dump_stack() implementations and unify their behaviors
Both dump_stack() and show_stack() are currently implemented by each
architecture.  show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack().  On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.

The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().

There's no reason to require archs to implement two separate but mostly
identical functions.  It leads to unnecessary subtle information.

This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin.  Blackfin's
dump_stack() does something wonky that I don't understand.

Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information.  This is used
in blackfin.

This patch brings the following behavior changes.

* On some archs, an extra level in backtrace for show_stack() could be
  printed.  This is because the top frame was determined in
  dump_stack() on those archs while generic dump_stack() can't do that
  reliably.  It can be compensated by inlining dump_stack() but not
  sure whether that'd be necessary.

* Most archs didn't use to print debug info on dump_stack().  They do
  now.

An example WARN dump follows.

 WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
 Hardware name: empty
 Modules linked in:
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
  0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
  ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
  0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
 Call Trace:
  [<ffffffff81c614dc>] dump_stack+0x19/0x1b
  [<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
  [<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
  [<ffffffff8234a071>] init_workqueues+0x35/0x505
  ...

v2: CPU number added to the generic debug info as requested by s390
    folks and dropped the s390 specific dump_stack().  This loses %ksp
    from the debug message which the maintainers think isn't important
    enough to keep the s390-specific dump_stack() implementation.

    dump_stack_print_info() is moved to kernel/printk.c from
    lib/dump_stack.c.  Because linkage is per objecct file,
    dump_stack_print_info() living in the same lib file as generic
    dump_stack() means that archs which implement custom dump_stack()
    - at this point, only blackfin - can't use dump_stack_print_info()
    as that will bring in the generic version of dump_stack() too.  v1
    The v1 patch broke build on blackfin due to this issue.  The build
    breakage was reported by Fengguang Wu.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>	[s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org>		[hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-30 17:04:02 -07:00
Linus Torvalds 9626357371 Changes for arch/xtensa for the 3.9 merge window.
Added features:
 - add support for thread local storage (TLS)
 - add accept4 and finit_module syscalls
 - support medium-priority interrupts
 - add support for dc232c processor variant
 - support file-base simulated disk for ISS simulator
 
 Bug fixes:
 - fix return values returned by the  str[n]cmp functions
 - avoid mmap cache aliasing
 - fix handling of 'windowed registers' in ptrace
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Merge tag 'xtensa-next-20130225' of git://github.com/czankel/xtensa-linux

Pull xtensa update from Chris Zankel:
 "Added features:
   - add support for thread local storage (TLS)

   - add accept4 and finit_module syscalls

   - support medium-priority interrupts

   - add support for dc232c processor variant

   - support file-base simulated disk for ISS simulator

  Bug fixes:

   - fix return values returned by the str[n]cmp functions

   - avoid mmap cache aliasing

   - fix handling of 'windowed registers' in ptrace"

* tag 'xtensa-next-20130225' of git://github.com/czankel/xtensa-linux:
  xtensa: add accept4 syscall
  xtensa: add support for TLS
  xtensa: add missing include asm/uaccess.h to checksum.h
  xtensa: do not enable GENERIC_GPIO by default
  xtensa: complete ptrace handling of register windows
  xtensa: add support for oprofile
  xtensa: move spill_registers to traps.h
  xtensa: ISS: add host file-based simulated disk
  xtensa: fix str[n]cmp return value
  xtensa: avoid mmap cache aliasing
  xtensa: add finit_module syscall
  xtensa: pull signal definitions from signal-defs.h
  xtensa: fix ipc_parse_version selection
  xtensa: dispatch medium-priority interrupts
  xtensa: Add config files for Diamond 233L - Rev C processor variant
  xtensa: use new common dtc rule
  xtensa: rename prom_update_property to of_update_property
2013-02-26 19:53:12 -08:00
Max Filippov 2d6f82fee4 xtensa: move spill_registers to traps.h
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2013-02-23 19:22:48 -08:00
Marc Gauthier 2d1c645cc5 xtensa: dispatch medium-priority interrupts
Add support for dispatching medium-priority interrupts, that is,
interrupts of priority levels 2 to EXCM_LEVEL. IRQ handling may be
preempted by higher priority IRQ.

Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2013-02-23 19:12:52 -08:00
Rusty Russell 373d4d0997 taint: add explicit flag to show whether lock dep is still OK.
Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-01-21 17:17:57 +10:30
Chris Zankel c4c4594b00 xtensa: clean up files to make them code-style compliant
Remove heading and trailing spaces, trim trailing lines, and wrap lines
that are longer than 80 characters.

Signed-off-by: Chris Zankel <chris@zankel.net>
2012-12-18 21:10:25 -08:00
Max Filippov 28570e8dac xtensa: add trap_set_handler function
trap_set_handler sets new C-handler in the exception table and returns
previous handler.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2012-12-18 21:10:22 -08:00
Max Filippov 4ded6282ca xtensa: fix unaligned usermode access
- correct use of .config #define name;
      CONFIG_UNALIGNED_USER ---> CONFIG_XTENSA_UNALIGNED_USER

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Pete Delaney <piet@tensilica.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2012-10-15 21:48:41 -07:00
Max Filippov bc5378fcba xtensa: reorganize SR referencing
- reference SRs by names where possible, not by numbers;
- get rid of __stringify around SR names where possible;
- remove unneeded SR names from asm/regs.h;
- add SREG_ prefix to remaining SR names;

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2012-10-15 21:48:08 -07:00
David Howells f9aa7e1882 Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Xtensa.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Chris Zankel <chris@zankel.net>
2012-03-28 18:30:03 +01:00
Joe Perches ad361c9884 Remove multiple KERN_ prefixes from printk formats
Commit 5fd29d6ccb ("printk: clean up
handling of log-levels and newlines") changed printk semantics.  printk
lines with multiple KERN_<level> prefixes are no longer emitted as
before the patch.

<level> is now included in the output on each additional use.

Remove all uses of multiple KERN_<level>s in formats.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-08 10:30:03 -07:00
Johannes Weiner 586411dcd1 xtensa: always use correct stack pointer for stack traces
Commit '28a0ce7 xtensa: use correct stack pointer for stack traces'
changed the stack tracer from always reading the stack pointer
register to always using the saved value in the task descriptor.

The author was too dense to consider the fact that the saved stack
value is stale for a running process und thus unusable for 'current'.

What we do now is to use the stack pointer register (a1) for when the
task is unknown - we can't help it then - or when the task is
'current'.  For everything else use the saved stack pointer value
contained in the task descriptor.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2009-05-11 21:59:43 -07:00
Johannes Weiner e5083a63b6 xtensa: nommu support
Add support for !CONFIG_MMU setups.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2009-04-02 23:41:50 -07:00
Johannes Weiner 28a0ce7f64 xtensa: use correct stack pointer for stack traces
Right now, the xtensa stacktrace code reads the _current_ kernel stack
pointer if nothing is supplied.  With debugging facilities like sysrq
this means that the backtrace of the sysrq-handler is printed instead
of a trace of the given task's stack.

When no stack pointer is specified in show_trace() and show_stack(),
use the stack pointer that comes with the handed in task descriptor to
make stack traces more useful.

Signed-off-by: Johannes Weiner <jw@emlix.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
2009-04-02 23:38:57 -07:00
Alexey Dobriyan 5a891ed5ad xtensa: fix compilation somewhat
* ->put_char changes
 * HIGHMEM is bogus it seems, there is no kmap_atomic() et al
 * some includes

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Chris Zankel <zankel@tensilica.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-10 15:55:10 -07:00
Chris Zankel c658eac628 [XTENSA] Add support for configurable registers and coprocessors
The Xtensa architecture allows to define custom instructions and
registers. Registers that are bound to a coprocessor are only
accessible if the corresponding enable bit is set, which allows
to implement a 'lazy' context switch mechanism. Other registers
needs to be saved and restore at the time of the context switch
or during interrupt handling.

This patch adds support for these additional states:

- save and restore registers that are used by the compiler upon
  interrupt entry and exit.
- context switch additional registers unbound to any coprocessor
- 'lazy' context switch of registers bound to a coprocessor
- ptrace interface to provide access to additional registers
- update configuration files in include/asm-xtensa/variant-fsf

Signed-off-by: Chris Zankel <chris@zankel.net>
2008-02-13 17:41:43 -08:00
Chris Zankel 8d7e8240e6 [XTENSA] Clean up elf-gregset.
Remove additional registers from the ELF gregset structure that
are only used by the kernel or are not required or invalid in
user-space. The ar registers are always aligned to a windowbase
value of 0, and the WB register is always assumed to be 0.
Increase the size of the structure to 128 entries. This will
provide enough space in future.

Signed-off-by: Chris Zankel <chris@zankel.net>
2008-02-13 17:09:08 -08:00
Alexey Dobriyan 19c5870c0e Use helpers to obtain task pid in printks (arch code)
One of the easiest things to isolate is the pid printed in kernel log.
There was a patch, that made this for arch-independent code, this one makes
so for arch/xxx files.

It took some time to cross-compile it, but hopefully these are all the
printks in arch code.

Signed-off-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-19 11:53:43 -07:00
Chris Zankel b91dc336cc [XTENSA] fix wrong usage of __init and __initdata in traps.c
A variable was defined with __init instead of __initdata and
the function accessing that variable wasn't initialized with
__init.

Signed-off-by: Chris Zankel <chris@zankel.net>
2007-08-27 13:52:49 -07:00
Pavel Emelianov bcdcd8e725 Report that kernel is tainted if there was an OOPS
If the kernel OOPSed or BUGed then it probably should be considered as
tainted.  Thus, all subsequent OOPSes and SysRq dumps will report the
tainted kernel.  This saves a lot of time explaining oddities in the
calltraces.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Added parisc patch from Matthew Wilson  -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-17 10:23:02 -07:00
Chris Zankel 173d668138 [PATCH] xtensa: remove extra header files
The Xtensa port contained many header files that were never needed.  This
rather lengthy patch removes all those files.  Unfortunately, there were
many dependencies that needed to be updated, so this patch touches quite a
few source files.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10 09:55:39 -08:00
Horms 012c437d03 [PATCH] Change panic_on_oops message to "Fatal exception"
Previously the message was "Fatal exception: panic_on_oops", as introduced
in a recent patch whith removed a somewhat dangerous call to ssleep() in
the panic_on_oops path.  However, Paul Mackerras suggested that this was
somewhat confusing, leadind people to believe that it was panic_on_oops
that was the root cause of the fatal exception.  On his suggestion, this
patch changes the message to simply "Fatal exception".  A suitable oops
message should already have been displayed.

Signed-off-by: Simon Horman <horms@verge.net.au>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-08-14 12:54:29 -07:00