commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.
The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.
That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works. However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.
In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV. And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.
However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space. And user space really
expected SIGSEGV, not SIGBUS.
To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it. They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.
This is the mindless minimal patch to do this. A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.
Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.
Reported-and-tested-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Jan Engelhardt <jengelh@inai.de>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Lennox Wu <lennox.wu@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull timer fixes from Ingo Molnar: "Main changes: - Fix the deadlock reported by Dave Jones et al - Clean up and fix nohz_full interaction with arch abilities - nohz init code consolidation/cleanup" * 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: nohz: nohz full depends on irq work self IPI support nohz: Consolidate nohz full init code arm64: Tell irq work about self IPI support arm: Tell irq work about self IPI support x86: Tell irq work about self IPI support irq_work: Force raised irq work to run on irq work interrupt irq_work: Introduce arch_irq_work_has_interrupt() nohz: Move nohz full init call to tick init
The symbol is an orphan, get rid of it. Signed-off-by: Richard Weinberger <richard@nod.at> Acked-by: Lennox Wu <lennox.wu@gmail.com> Cc: Paul Bolle <pebolle@tiscali.nl> [Guenter Roeck: Merge with 3.17-rc3; update headline] Signed-off-by: Guenter Roeck <linux@roeck-us.net>
The related error (with allmodconfig under score):
CC [M] drivers/staging/speakup/speakup_acntpc.o
In file included from drivers/staging/speakup/speakup_acntpc.c:33:0:
drivers/staging/speakup/serialio.h:7:24: fatal error: asm/serial.h: No such file or directory
#include <asm/serial.h>
^
compilation terminated.
make[3]: *** [drivers/staging/speakup/speakup_acntpc.o] Error 1
make[2]: *** [drivers/staging/speakup] Error 2
make[1]: *** [drivers/staging] Error 2
make: *** [drivers] Error 2
Acked-by: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
This patch removes the use of the IRQF_DISABLED flag from arch/score/kernel/time.c It's a NOOP since 2.6.35 and it will be removed one day. Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Acked-by: Lennox Wu <lennox.wu@gmail.com>
The related error (with allmodconfig under score):
MODPOST 1365 modules
ERROR: "flush_icache_range" [drivers/misc/lkdtm.ko] undefined!
Acked-by: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
'csum_partial_copy_from_user' and 'flush_dcache_page' are also needed by
outside modules, so need export them in the related files.
The related error (with allmodconfig under score):
MODPOST 1365 modules
ERROR: "csum_partial_copy_from_user" [net/rxrpc/af-rxrpc.ko] undefined!
ERROR: "flush_dcache_page" [net/sunrpc/sunrpc.ko] undefined!
Acked-by: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
The nohz full code needs irq work to trigger its own interrupt so that the subsystem can work even when the tick is stopped. Lets introduce arch_irq_work_has_interrupt() that archs can override to tell about their support for this ability. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Pull arch signal handling cleanup from Richard Weinberger: "This patch series moves all remaining archs to the get_signal(), signal_setup_done() and sigsp() functions. Currently these archs use open coded variants of the said functions. Further, unused parameters get removed from get_signal_to_deliver(), tracehook_signal_handler() and signal_delivered(). At the end of the day we save around 500 lines of code." * 'signal-cleanup' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/misc: (43 commits) powerpc: Use sigsp() openrisc: Use sigsp() mn10300: Use sigsp() mips: Use sigsp() microblaze: Use sigsp() metag: Use sigsp() m68k: Use sigsp() m32r: Use sigsp() hexagon: Use sigsp() frv: Use sigsp() cris: Use sigsp() c6x: Use sigsp() blackfin: Use sigsp() avr32: Use sigsp() arm64: Use sigsp() arc: Use sigsp() sas_ss_flags: Remove nested ternary if Rip out get_signal_to_deliver() Clean up signal_delivered() tracehook_signal_handler: Remove sig, info, ka and regs ...