Commit graph

382 commits

Author SHA1 Message Date
Richard Henderson
d551b822f7 accel/tcg: Use vaddr in cpu_loop.h
Use vaddr instead of abi_ptr or target_ulong for a guest address.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2025-05-05 09:24:06 -07:00
Philippe Mathieu-Daudé
18b3abb722 user: Prefer cached CpuClass over CPU_GET_CLASS() macro
CpuState caches its CPUClass since commit 6fbdff8706
("cpu: cache CPUClass in CPUState for hot code paths"),
use it.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250122093028.52416-7-philmd@linaro.org>
2025-03-09 17:00:47 +01:00
Philippe Mathieu-Daudé
1501743654 accel/tcg: Rename 'hw/core/tcg-cpu-ops.h' -> 'accel/tcg/cpu-ops.h'
TCGCPUOps structure makes more sense in the accelerator context
rather than hardware emulation. Move it under the accel/tcg/ scope.

Mechanical change doing:

 $  sed -i -e 's,hw/core/tcg-cpu-ops.h,accel/tcg/cpu-ops.h,g' \
   $(git grep -l hw/core/tcg-cpu-ops.h)

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20250123234415.59850-11-philmd@linaro.org>
2025-03-06 15:46:17 +01:00
Ilya Leoshkevich
2b3ccf5f0d user: Introduce host_interrupt_signal
Attaching to the gdbstub of a running process requires stopping its
threads. For threads that run on a CPU, cpu_exit() is enough, but the
only way to grab attention of a thread that is stuck in a long-running
syscall is to interrupt it with a signal.

Reserve a host realtime signal for this, just like it's already done
for TARGET_SIGABRT on Linux. This may reduce the number of available
guest realtime signals by one, but this is acceptable, since there are
quite a lot of them, and it's unlikely that there are apps that need
them all.

Set signal_pending for the safe_sycall machinery to prevent invoking
the syscall. This is a lie, since we don't queue a guest signal, but
process_pending_signals() can handle the absence of pending signals.
The syscall returns with QEMU_ERESTARTSYS errno, which arranges for
the automatic restart. This is important, because it helps avoiding
disturbing poorly written guests.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20250117001542.8290-5-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-14-alex.bennee@linaro.org>
2025-02-10 13:47:59 +00:00
Ilya Leoshkevich
08916fd4b6 user: Introduce user/signal.h
gdbstub needs target_to_host_signal(), so move its declaration to a
public header.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20250117001542.8290-4-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20250207153112.3939799-13-alex.bennee@linaro.org>
2025-02-10 13:47:59 +00:00
Philippe Mathieu-Daudé
1bf0d6e476 user: Move various declarations out of 'exec/exec-all.h'
Move various declarations related to user emulation
from "exec/exec-all.h" to "user/cpu_loop.h".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-19-philmd@linaro.org>
2024-12-20 17:44:57 +01:00
Philippe Mathieu-Daudé
f47dcf519d accel/tcg: Move user-related declarations out of 'exec/cpu-all.h' (4/4)
Move declarations related to page protection under user
emulation from "exec/cpu-all.h" to "user/page-protection.h".

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20241212185341.2857-15-philmd@linaro.org>
2024-12-20 17:44:57 +01:00
Ilya Leoshkevich
c107521e0e linux-user: Allow custom rt signal mappings
Some applications want to use low priority realtime signals (e.g.,
SIGRTMAX). Currently QEMU cannot map all target realtime signals to
host realtime signals, and chooses to sacrifice the end of the target
realtime signal range.

Allow users to choose how to map target realtime signals to host
realtime signals using the new -t option, the new QEMU_RTSIG_MAP
environment variable, and the new -Drtsig_map=\"...\" meson flag.
To simplify things, the meson flag is not per-target, because the
intended use case is app-specific qemu-user builds.

The mapping is specified using the "tsig hsig count[,...]" syntax.
Target realtime signals [tsig,tsig+count) are mapped to host realtime
signals [hsig,hsig+count). Care is taken to avoid double and
out-of-range mappings.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20241029232211.206766-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-11-05 10:36:08 +00:00
Philippe Mathieu-Daudé
74781c0888 exec/cpu: Extract page-protection definitions to page-protection.h
Extract page-protection definitions from "exec/cpu-all.h"
to "exec/page-protection.h".

The list of files requiring the new header was generated
using:

$ git grep -wE \
  'PAGE_(READ|WRITE|EXEC|RWX|VALID|ANON|RESERVED|TARGET_.|PASSTHROUGH)'

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240427155714.53669-3-philmd@linaro.org>
2024-05-06 11:17:15 +02:00
Richard Henderson
143bcc1d59 linux-user: Preserve unswapped siginfo_t for strace
Passing the tswapped structure to strace means that
our internal si_type is also gone, which then aborts
in print_siginfo.

Fixes: 4d6d8a05a0 ("linux-user: Move tswap_siginfo out of target code")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-04-09 07:47:11 -10:00
Gustavo Romero
f84e313e02 gdbstub: Save target's siginfo
Save target's siginfo into gdbserver_state so it can be used later, for
example, in any stub that requires the target's si_signo and si_code.

This change affects only linux-user mode.

Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240309030901.1726211-4-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2024-03-13 11:43:52 +00:00
Gustavo Romero
4d6d8a05a0 linux-user: Move tswap_siginfo out of target code
Move tswap_siginfo from target code to handle_pending_signal. This will
allow some cleanups and having the siginfo ready to be used in gdbstub.

Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240309030901.1726211-3-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2024-03-13 11:43:52 +00:00
Gustavo Romero
b6617e937e gdbstub: Rename back gdb_handlesig
Rename gdb_handlesig_reason back to gdb_handlesig. There is no need to
add a wrapper for gdb_handlesig and rename it when a new parameter is
added.

Signed-off-by: Gustavo Romero <gustavo.romero@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240309030901.1726211-2-gustavo.romero@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
2024-03-13 11:43:52 +00:00
Philippe Mathieu-Daudé
42e62aadfd user: Prefer fast cpu_env() over slower CPU QOM cast macro
Mechanical patch produced running the command documented
in scripts/coccinelle/cpu_env.cocci_template header.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-ID: <20240129164514.73104-30-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2024-03-12 12:04:25 +01:00
Ilya Leoshkevich
e4e5cb4a54 {linux,bsd}-user: Introduce get_task_state()
A CPU's TaskState is stored in the CPUState's void *opaque field,
accessing which is somewhat awkward due to having to use a cast.
Introduce a wrapper and use it everywhere.

Suggested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240219141628.246823-3-iii@linux.ibm.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-4-alex.bennee@linaro.org>
2024-03-06 12:35:19 +00:00
Richard Henderson
1764ad70ce include/qemu: Add TCGCPUOps typedef to typedefs.h
QEMU coding style recommends using structure typedefs.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-01-29 21:04:10 +10:00
Robbin Ehn
6d913158b5 linux-user: Fixed cpu restore with pc 0 on SIGBUS
Commit f4e1168198 (linux-user: Split out host_sig{segv,bus}_handler)
introduced a bug, when returning from host_sigbus_handler the PC is
never set. Thus cpu_loop_exit_restore is called with a zero PC and
we immediate get a SIGSEGV.

Signed-off-by: Robbin Ehn <rehn@rivosinc.com>
Fixes: f4e1168198 ("linux-user: Split out host_sig{segv,bus}_handler")
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Message-Id: <33f27425878fb529b9e39ef22c303f6e0d90525f.camel@rivosinc.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-01-23 13:22:46 +10:00
Richard Henderson
02d9f5b6ac linux-user: Fix guest signal remapping after adjusting SIGABRT
The arithmetic within the loop was not adjusted properly after SIGRTMIN
was stolen for the guest SIGABRT.  The effect was that the guest libc
could not send itself __SIGRTMIN to wake sleeping threads.

Fixes: 38ee0a7dfb ("linux-user: Remap guest SIGABRT")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1967
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:40:35 -07:00
Richard Henderson
38ee0a7dfb linux-user: Remap guest SIGABRT
Distinguish host SIGABRT from guest SIGABRT by mapping
the guest signal onto one of the host RT signals.

This prevents a cycle by which a host assertion failure
is caught and handled by host_signal_handler, queued for
the guest, and then we attempt to continue past the
host abort.  What happens next depends on the host libc,
but is neither good nor helpful.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 16:25:06 -07:00
Richard Henderson
4a6ebc19a7 linux-user: Detect and report host SIGILL, SIGFPE, SIGTRAP
These signals, when not spoofed via kill(), are always bugs.
Use die_from_signal to report this sensibly.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:34:34 -07:00
Richard Henderson
f4e1168198 linux-user: Split out host_sig{segv,bus}_handler
Make host_signal_handler slightly easier to read.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:34:28 -07:00
Richard Henderson
58c4e36c4e linux-user: Simplify signal_init
Install the host signal handler at the same time we are
probing the target signals for SIG_IGN/SIG_DFL.  Ignore
unmapped target signals.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:34:12 -07:00
Richard Henderson
b60b91aa8f linux-user: Map unsupported signals to an out-of-bounds value
Do not return a valid signal number in one domain
when given an invalid signal number in the other domain.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:33:59 -07:00
Richard Henderson
dbde2c0c0e linux-user: Only register handlers for core_dump_signal by default
The set of fatal signals is really immaterial.  If one arrives,
and is unhandled, then the qemu process dies and the parent gets
the correct signal.

It is only for those signals which we would like to perform a
guest core dump instead of a host core dump that we need to catch.

Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:33:53 -07:00
Helge Deller
7dfd3ca8d9 linux-user: Detect and report host crashes
If there is an internal program error in the qemu source code which
raises SIGSEGV or SIGBUS, we currently assume the signal belongs to
the guest.  With an artificial error introduced, we will now print

   QEMU internal SIGSEGV {code=MAPERR, addr=(nil)}

Signed-off-by: Helge Deller <deller@gmx.de>
Message-Id: <20230812164314.352131-1-deller@gmx.de>
[rth: Use in_code_gen_buffer and die_with_signal; drop backtrace]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:33:45 -07:00
Richard Henderson
ee72c47eeb linux-user: Exit not abort in die_with_backtrace
This line is supposed to be unreachable, but if we're going to
have it at all, SIGABRT via abort() is subject to the same signal
peril that created this function in the first place.

We can _exit immediately without peril.

Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:33:41 -07:00
Richard Henderson
b8b50f1e9a linux-user: Split out die_with_signal
Because we trap so many signals for use by the guest,
we have to take extra steps to exit properly.

Acked-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-18 15:33:30 -07:00
Richard Henderson
a0bc599726 build: Remove --enable-gprof
This build option has been deprecated since 8.0.
Remove all CONFIG_GPROF code that depends on that,
including one errant check using TARGET_GPROF.

Acked-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-04 11:03:54 -07:00
Richard Henderson
b77af26e97 accel/tcg: Replace CPUState.env_ptr with cpu_env()
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-04 11:03:54 -07:00
Alex Bennée
d96bf49ba8 gdbstub: move chunks of user code into own files
The process was pretty similar to the softmmu move except we take the
time to split stuff between user.c and user-target.c to avoid as much
target specific compilation as possible. We also start to make use of
our shiny new header scheme so the user-only helpers can be included
without the rest of the exec/gsbstub.h cruft.

As before we split some functions into user and softmmu versions

Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-12-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-12-richard.henderson@linaro.org>
2023-03-07 20:44:04 +00:00
Ilya Leoshkevich
da91c19202 linux-user: Clean up when exiting due to a signal
When exiting due to an exit() syscall, qemu-user calls
preexit_cleanup(), but this is currently not the case when exiting due
to a signal. This leads to various buffers not being flushed (e.g.,
for gprof, for gcov, and for the upcoming perf support).

Add the missing call.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230112152013.125680-2-iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-01-16 10:14:12 -10:00
Helge Deller
7b72aa1d81 linux-user: Add missing signals in strace output
Some of the guest signal numbers are currently not converted to
their representative names in the strace output, e.g. SIGVTALRM.

This patch introduces a smart way to generate and keep in sync the
host-to-guest and guest-to-host signal conversion tables for usage in
the qemu signal and strace code. This ensures that any signals
will now show up in both tables.

There is no functional change in this patch - with the exception that yet
missing signal names now show up in the strace code too.

Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20220918194555.83535-2-deller@gmx.de>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-09-27 09:29:33 +02:00
Marc-André Lureau
8905770b27 compiler.h: replace QEMU_NORETURN with G_NORETURN
G_NORETURN was introduced in glib 2.68, fallback to G_GNUC_NORETURN in
glib-compat.

Note that this attribute must be placed before the function declaration
(bringing a bit of consistency in qemu codebase usage).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20220420132624.2439741-20-marcandre.lureau@redhat.com>
2022-04-21 17:03:51 +04:00
Richard Henderson
0a99f09383 linux-user: Split out helpers for sigsuspend
Two new functions: process_sigsuspend_mask and finish_sigsuspend_mask.
Move the size check and copy-from-user code.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20220315084308.433109-3-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-03-22 13:06:21 +01:00
Peter Maydell
4ff17cf0aa linux-user: Remove stale "not threadsafe" comments
In linux-user/signal.c we have two FIXME comments claiming that
parts of the signal-handling code are not threadsafe. These are
very old, as they were first introduced in commit 624f797905
in 2008. Since then we've radically overhauled the signal-handling
logic, while carefully preserving these FIXME comments.

It's unclear exactly what thread-safety issue the original
author was trying to point out -- the relevant data structures
are in the TaskStruct, which makes them per-thread and only
operated on by that thread. The old code at the time of that
commit did have various races involving signal handlers being
invoked at awkward times; possibly this was what was meant.

Delete these FIXME comments:
 * they were written at a time when the way we handled
   signals was completely different
 * the code today appears to us to not have thread-safety issues
 * nobody knows what the problem the comments were trying to
   point out was
so they are serving no useful purpose for us today.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Message-Id: <20220114155032.3767771-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-03-08 16:01:08 +01:00
Richard Henderson
9940799bde linux-user: Introduce host_sigcontext
Do not directly access ucontext_t as the third signal parameter.
This is preparation for a sparc64 fix.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-02-09 08:47:48 +11:00
Richard Henderson
c8c89a6a30 linux-user: Introduce host_signal_mask
Do not directly access the uc_sigmask member.
This is preparation for a sparc64 fix.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2022-02-09 08:47:09 +11:00
Peter Maydell
337e88d890 linux-user: Return void from queue_signal()
The linux-user queue_signal() function always returns 1, and none of
its callers check the return value.  Give it a void return type
instead.

The return value is a leftover from the old pre-2016 linux-user
signal handling code, which really did have a queue of signals and so
might return a failure indication if too many signals were queued at
once.  The current design avoids having to ever have more than one
signal queued via queue_signal() at once, so it can never fail.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220114153732.3767229-4-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-01-18 12:42:28 +01:00
Peter Maydell
b5f9536643 linux-user: Rename user_force_sig tracepoint to match function name
In commit c599d4d6d6 in 2016 we renamed the old force_sig()
function to dump_core_and_abort(), but we forgot to rename the
associated tracepoint.  Rename the tracepoint to to match the
function it's called from.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220114153732.3767229-3-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-01-18 12:41:42 +01:00
Richard Henderson
155fff93f8 linux-user/nios2: Use set_sigmask in do_rt_sigreturn
Using do_sigprocmask directly was incorrect, as it will
leave the signal blocked by the outer layers of linux-user.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211221025012.1057923-8-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-01-06 11:40:52 +01:00
Matthias Schiffer
139e5de7c8 linux-user/signal: Map exit signals in SIGCHLD siginfo_t
When converting a siginfo_t from waitid(), the interpretation of si_status
depends on the value of si_code: For CLD_EXITED, it is an exit code and
should be copied verbatim. For other codes, it is a signal number
(possibly with additional high bits from ptrace) that should be mapped.

This code was previously changed in commit 1c3dfb506e
("linux-user/signal: Decode waitid si_code"), but the fix was
incomplete.

Tested with the following test program:

    #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <sys/wait.h>

    int main() {
    	pid_t pid = fork();
    	if (pid == 0) {
    		exit(12);
    	} else {
    		siginfo_t siginfo = {};
    		waitid(P_PID, pid, &siginfo, WEXITED);
    		printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status);
    	}

    	pid = fork();
    	if (pid == 0) {
    		raise(SIGUSR2);
    	} else {
    		siginfo_t siginfo = {};
    		waitid(P_PID, pid, &siginfo, WEXITED);
    		printf("Code: %d, status: %d\n", (int)siginfo.si_code, (int)siginfo.si_status);
    	}
    }

Output with an x86_64 host and mips64el target before 1c3dfb506e
(incorrect: exit code 12 is translated like a signal):

    Code: 1, status: 17
    Code: 2, status: 17

After 1c3dfb506e (incorrect: signal number is not translated):

    Code: 1, status: 12
    Code: 2, status: 12

With this patch:

    Code: 1, status: 12
    Code: 2, status: 17

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <81534fde7cdfc6acea4889d886fbefdd606630fb.1635019124.git.mschiffer@universe-factory.net>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-01-06 11:40:52 +01:00
Richard Henderson
bbf15aaf7c common-user: Move safe-syscall.* from linux-user
Move linux-user safe-syscall.S and safe-syscall-error.c to common-user
so that bsd-user can also use it.  Also move safe-syscall.h to
include/user/.  Since there is nothing here that is related to the guest,
as opposed to the host, build it once.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-12-20 10:12:24 -08:00
Richard Henderson
af254a2792 linux-user: Rename TARGET_ERESTARTSYS to QEMU_ERESTARTSYS
This value is fully internal to qemu, and so is not a TARGET define.
We use this as an extra marker for both host and target errno.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-12-19 20:47:33 -08:00
Richard Henderson
0a7e01904d linux-user: Remove HAVE_SAFE_SYSCALL and hostdep.h
All supported hosts now define HAVE_SAFE_SYSCALL, so remove
the ifdefs.  This leaves hostdep.h empty, so remove it.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-12-19 20:47:33 -08:00
Warner Losh
0763788868 linux-user/signal.c: Create a common rewind_if_in_safe_syscall
All instances of rewind_if_in_safe_syscall are the same, differing only
in how the instruction point is fetched from the ucontext and the size
of the registers. Use host_signal_pc and new host_signal_set_pc
interfaces to fetch the pointer to the PC and adjust if needed. Delete
all the old copies of rewind_if_in_safe_syscall.

Acked-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20211113045603.60391-3-imp@bsdimp.com>
[rth: include safe-syscall.h, simplify ifdefs]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-23 01:47:20 +01:00
Richard Henderson
742f07628c linux-user: Handle BUS_ADRALN in host_signal_handler
Handle BUS_ADRALN via cpu_loop_exit_sigbus, but allow other SIGBUS
si_codes to continue into the host-to-guest signal conversion code.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-02 07:00:52 -04:00
Richard Henderson
12ed56407e linux-user: Add cpu_loop_exit_sigbus
This is a new interface to be provided by the os emulator for
raising SIGBUS on fault.  Use the new record_sigbus target hook.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-02 07:00:52 -04:00
Richard Henderson
eeca7dc566 accel/tcg: Restrict TCGCPUOps::tlb_fill() to sysemu
We have replaced tlb_fill with record_sigsegv for user mode.
Move the declaration to restrict it to system emulation.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-02 07:00:52 -04:00
Richard Henderson
72d2bbf9ff linux-user: Add cpu_loop_exit_sigsegv
This is a new interface to be provided by the os emulator for
raising SIGSEGV on fault.  Use the new record_sigsegv target hook.

Reviewed by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-02 07:00:52 -04:00
Richard Henderson
04de121aaf linux-user/signal: Drop HOST_SIGNAL_PLACEHOLDER
Now that all of the linux-user hosts have been converted
to host-signal.h, drop the compatibility code.

Reviewed by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2021-11-02 07:00:52 -04:00