qemu/linux-user
Timothy E Baldwin 655ed67c2a linux-user: Queue synchronous signals separately
If a synchronous signal and an asynchronous signal arrive near simultaneously,
and the signal number of the asynchronous signal is lower than that of the
synchronous signal the the handler for the asynchronous would be called first,
and then the handler for the synchronous signal would be called within or
after the first handler with an incorrect context.

This is fixed by queuing synchronous signals separately. Note that this does
risk delaying a asynchronous signal until the synchronous signal handler
returns rather than handling the signal on another thread, but this seems
unlikely to cause problems for real guest programs and is unavoidable unless
we could guarantee to roll back and reexecute whatever guest instruction
caused the synchronous signal (which would be a bit odd if we've already
logged its execution, for instance, and would require careful analysis of
all guest CPUs to check it was possible in all cases).

Signed-off-by: Timothy Edward Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Message-id: 1441497448-32489-24-git-send-email-T.E.Baldwin99@members.leeds.ac.uk
[PMM: added a comment]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
2016-06-07 16:39:07 +03:00
..
aarch64 linux-user: remove unavailable syscalls from aarch64 2016-02-23 21:25:10 +02:00
alpha linux-user: Support for restarting system calls for Alpha targets 2016-05-27 14:49:50 +03:00
arm linux-user: arm: Remove ARM_cpsr and similar #defines 2016-05-27 14:50:39 +03:00
cris linux-user: Support for restarting system calls for CRIS targets 2016-05-27 14:49:50 +03:00
host linux-user: Provide safe_syscall for fixing races between signals and syscalls 2016-05-27 14:49:51 +03:00
i386 linux-user: correct timerfd_create syscall numbers 2016-02-23 21:25:10 +02:00
m68k linux-user: Support for restarting system calls for M68K targets 2016-05-27 14:49:50 +03:00
microblaze linux-user: Support for restarting system calls for Microblaze targets 2016-05-27 14:49:51 +03:00
mips linux-user: Support for restarting system calls for MIPS targets 2016-05-27 14:49:49 +03:00
mips64 linux-user: Support for restarting system calls for MIPS targets 2016-05-27 14:49:49 +03:00
openrisc linux-user: Support for restarting system calls for OpenRISC targets 2016-05-27 14:49:50 +03:00
ppc linux-user: Support for restarting system calls for PPC targets 2016-05-27 14:49:49 +03:00
s390x linux-user: Support for restarting system calls for S390 targets 2016-05-27 14:49:50 +03:00
sh4 linux-user: Support for restarting system calls for SH4 targets 2016-05-27 14:49:49 +03:00
sparc linux-user: Support for restarting system calls for SPARC targets 2016-05-27 14:49:49 +03:00
sparc64 linux-user: Support for restarting system calls for SPARC targets 2016-05-27 14:49:49 +03:00
tilegx linux-user: Support for restarting system calls for tilegx targets 2016-05-27 14:49:50 +03:00
unicore32 build: [linux-user] Rename "syscall.h" to "target_syscall.h" in target directories 2016-02-23 21:25:09 +02:00
x86_64 linux-user: correct timerfd_create syscall numbers 2016-02-23 21:25:10 +02:00
elfload.c linux-user: arm: Remove ARM_cpsr and similar #defines 2016-05-27 14:50:39 +03:00
errno_defs.h linux-user: Renumber TARGET_QEMU_ESIGRETURN, make it not arch-specific 2016-05-27 14:49:49 +03:00
flat.h Support for 32 bit ABI on 64 bit targets (only enabled Sparc64) 2007-10-14 16:27:31 +00:00
flatload.c osdep: add wrappers for socket functions 2016-03-10 17:19:07 +00:00
ioctls.h linux-user: Convert blkpg to use a special subop handler 2014-10-06 21:52:45 +03:00
linux_loop.h Fix build failure with old kernel headers (loop.h is incompatible with 2008-05-23 16:06:43 +00:00
linuxload.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00
m68k-sim.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00
main.c linux-user: Remove real-time signal queuing 2016-06-07 16:39:07 +03:00
Makefile.objs linux-user: Provide safe_syscall for fixing races between signals and syscalls 2016-05-27 14:49:51 +03:00
mmap.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00
qemu.h linux-user: Queue synchronous signals separately 2016-06-07 16:39:07 +03:00
safe-syscall.S linux-user: Provide safe_syscall for fixing races between signals and syscalls 2016-05-27 14:49:51 +03:00
signal.c linux-user: Queue synchronous signals separately 2016-06-07 16:39:07 +03:00
socket.h linux-user: support SO_PASSSEC setsockopt option 2014-06-29 14:19:59 +03:00
strace.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00
strace.list linux-user: add setns and unshare 2014-08-22 15:06:34 +03:00
syscall_defs.h linux-user: x86_64: Don't use 16-bit UIDs 2016-05-27 14:50:39 +03:00
syscall_types.h linux-user: Convert blkpg to use a special subop handler 2014-10-06 21:52:45 +03:00
syscall.c linux-user: Fix race between multiple signals 2016-06-07 16:39:07 +03:00
target_flat.h linux-user/FLAT: allow targets to override FLAT processing 2011-02-09 10:33:54 +02:00
uaccess.c util: move declarations out of qemu-common.h 2016-03-22 22:20:17 +01:00
uname.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00
uname.h linux-user: move uname functions to uname.c 2014-05-02 21:59:36 +03:00
vm86.c linux-user: Clean up includes 2016-01-29 15:07:22 +00:00