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.

Sig

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>

show more ...

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.

Sig

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>

show more ...

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.

Sig

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>

show more ...

linux-user/sh4: Fix crashes on signal delivery

sh4 uses gUSA (general UserSpace Atomicity) to provide atomicity on CPUs
that don't have atomic instructions. A gUSA region that adds 1 to an
atomic va

linux-user/sh4: Fix crashes on signal delivery

sh4 uses gUSA (general UserSpace Atomicity) to provide atomicity on CPUs
that don't have atomic instructions. A gUSA region that adds 1 to an
atomic variable stored in @R2 looks like this:

4004b6: 03 c7 mova 4004c4 <gusa+0x10>,r0
4004b8: f3 61 mov r15,r1
4004ba: 09 00 nop
4004bc: fa ef mov #-6,r15
4004be: 22 63 mov.l @r2,r3
4004c0: 01 73 add #1,r3
4004c2: 32 22 mov.l r3,@r2
4004c4: 13 6f mov r1,r15

R0 contains a pointer to the end of the gUSA region
R1 contains the saved stack pointer
R15 contains negative length of the gUSA region

When this region is interrupted by a signal, the kernel detects if
R15 >= -128U. If yes, the kernel rolls back PC to the beginning of the
region and restores SP by copying R1 to R15.

The problem happens if we are interrupted by a signal at address 4004c4.
R15 still holds the value -6, but the atomic value was already written by
an instruction at address 4004c2. In this situation we can't undo the
gUSA. The function unwind_gusa does nothing, the signal handler attempts
to push a signal frame to the address -6 and crashes.

This patch fixes it, so that if we are interrupted at the last instruction
in a gUSA region, we copy R1 to R15 to restore the correct stack pointer
and avoid crashing.

There's another bug: if we are interrupted in a delay slot, we save the
address of the instruction in the delay slot. We must save the address of
the previous instruction.

Cc: qemu-stable@nongnu.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Yoshinori Sato <ysato@users.sourcefoege.jp>
Message-Id: <b16389f7-6c62-70b7-59b3-87533c0bcc@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

linux-user/sh4: Fix crashes on signal delivery

sh4 uses gUSA (general UserSpace Atomicity) to provide atomicity on CPUs
that don't have atomic instructions. A gUSA region that adds 1 to an
atomic va

linux-user/sh4: Fix crashes on signal delivery

sh4 uses gUSA (general UserSpace Atomicity) to provide atomicity on CPUs
that don't have atomic instructions. A gUSA region that adds 1 to an
atomic variable stored in @R2 looks like this:

4004b6: 03 c7 mova 4004c4 <gusa+0x10>,r0
4004b8: f3 61 mov r15,r1
4004ba: 09 00 nop
4004bc: fa ef mov #-6,r15
4004be: 22 63 mov.l @r2,r3
4004c0: 01 73 add #1,r3
4004c2: 32 22 mov.l r3,@r2
4004c4: 13 6f mov r1,r15

R0 contains a pointer to the end of the gUSA region
R1 contains the saved stack pointer
R15 contains negative length of the gUSA region

When this region is interrupted by a signal, the kernel detects if
R15 >= -128U. If yes, the kernel rolls back PC to the beginning of the
region and restores SP by copying R1 to R15.

The problem happens if we are interrupted by a signal at address 4004c4.
R15 still holds the value -6, but the atomic value was already written by
an instruction at address 4004c2. In this situation we can't undo the
gUSA. The function unwind_gusa does nothing, the signal handler attempts
to push a signal frame to the address -6 and crashes.

This patch fixes it, so that if we are interrupted at the last instruction
in a gUSA region, we copy R1 to R15 to restore the correct stack pointer
and avoid crashing.

There's another bug: if we are interrupted in a delay slot, we save the
address of the instruction in the delay slot. We must save the address of
the previous instruction.

Cc: qemu-stable@nongnu.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Reviewed-by: Yoshinori Sato <ysato@users.sourcefoege.jp>
Message-Id: <b16389f7-6c62-70b7-59b3-87533c0bcc@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

target/sh4: Fix TB_FLAG_UNALIGN

The value previously chosen overlaps GUSA_MASK.

Rename all DELAY_SLOT_* and GUSA_* defines to emphasize
that they are included in TB_FLAGs. Add aliases for the
FPSC

target/sh4: Fix TB_FLAG_UNALIGN

The value previously chosen overlaps GUSA_MASK.

Rename all DELAY_SLOT_* and GUSA_* defines to emphasize
that they are included in TB_FLAGs. Add aliases for the
FPSCR and SR bits that are included in TB_FLAGS, so that
we don't accidentally reassign those bits.

Fixes: 4da06fb3062 ("target/sh4: Implement prctl_unalign_sigbus")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/856
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

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linux-user: Rename TARGET_QEMU_ESIGRETURN to QEMU_ESIGRETURN

This value is fully internal to qemu, and so is not a TARGET define.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mat

linux-user: Rename TARGET_QEMU_ESIGRETURN to QEMU_ESIGRETURN

This value is fully internal to qemu, and so is not a TARGET define.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

linux-user/sh4: Implement setup_sigtramp

Create and record the two signal trampolines.
Use them when the guest does not use SA_RESTORER.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Reviewed-by:

linux-user/sh4: Implement setup_sigtramp

Create and record the two signal trampolines.
Use them when the guest does not use SA_RESTORER.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210929130553.121567-23-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

show more ...

linux-user: Split linux-user internals out of qemu.h

qemu.h is included in various non-linux-user files (which
mostly want the TaskState struct and the functions for
doing usermode access to guest a

linux-user: Split linux-user internals out of qemu.h

qemu.h is included in various non-linux-user files (which
mostly want the TaskState struct and the functions for
doing usermode access to guest addresses like lock_user(),
unlock_user(), get_user*(), etc).

Split out the parts that are only used in linux-user itself
into a new user-internals.h. This leaves qemu.h with basically
three things:
* the definition of the TaskState struct
* the user-access functions and macros
* do_brk()
all of which are needed by code outside linux-user that
includes qemu.h.

The addition of all the extra #include lines was done with
sed -i '/include.*qemu\.h/a #include "user-internals.h"' $(git grep -l 'include.*qemu\.h' linux-user)
(and then undoing the change to fpa11.h).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210908154405.15417-8-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

show more ...

linux-user: Pass CPUArchState to target_restore_altstack

In most cases we were already passing get_sp_from_cpustate
directly to the function. In other cases, we were passing
a local variable which

linux-user: Pass CPUArchState to target_restore_altstack

In most cases we were already passing get_sp_from_cpustate
directly to the function. In other cases, we were passing
a local variable which already contained the same value.
In the rest of the cases, we were passing the stack pointer
out of env directly.

Reviewed by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210426025334.1168495-5-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

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linux-user: Use target_restore_altstack in all sigreturn

Note that target_restore_altstack uses the host memory
pointer that we have already verified, so TARGET_EFAULT
is not a possible return value

linux-user: Use target_restore_altstack in all sigreturn

Note that target_restore_altstack uses the host memory
pointer that we have already verified, so TARGET_EFAULT
is not a possible return value.

Note that using -EFAULT was a bug.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210426025334.1168495-3-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

show more ...

accel/tcg: Precompute curr_cflags into cpu->tcg_cflags

The primary motivation is to remove a dozen insns along
the fast-path in tb_lookup. As a byproduct, this allows
us to completely remove parall

accel/tcg: Precompute curr_cflags into cpu->tcg_cflags

The primary motivation is to remove a dozen insns along
the fast-path in tb_lookup. As a byproduct, this allows
us to completely remove parallel_cpus.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

linux-user: Remove dead error-checking code

Remove some dead code spotted by Coverity (CID 1009855,
1390854, 1390847). The underlying cause in all these cases
is the same: QEMU's put_user operations

linux-user: Remove dead error-checking code

Remove some dead code spotted by Coverity (CID 1009855,
1390854, 1390847). The underlying cause in all these cases
is the same: QEMU's put_user operations can't result in
errors, but the kernel's equivalent does. So when code
was copied from the kernel signal-frame-setup/teardown
code, checks on error flags that were needed in the kernel
became dead code for us.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20181019161715.12122-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

show more ...

linux-user: move get_sp_from_cpustate() to target_cpu.h

Remove useless includes
Fix HPPA include guard.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Acked-by: Richard Henderson <richard.hender

linux-user: move get_sp_from_cpustate() to target_cpu.h

Remove useless includes
Fix HPPA include guard.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180529194207.31503-9-laurent@vivier.eu>

show more ...

linux-user: introduce target_sigsp() and target_save_altstack()

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <201804111

linux-user: introduce target_sigsp() and target_save_altstack()

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180411192347.30228-1-laurent@vivier.eu>

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linux-user: move sh4 signal.c parts to sh4 directory

No code change, only move code from signal.c to
sh4/signal.c, except adding includes and
exporting setup_frame() and setup_rt_frame().

Signed-of

linux-user: move sh4 signal.c parts to sh4 directory

No code change, only move code from signal.c to
sh4/signal.c, except adding includes and
exporting setup_frame() and setup_rt_frame().

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180424192635.6027-5-laurent@vivier.eu>

show more ...

linux-user: create a dummy per arch signal.c

Create a signal-common.h for future use by these new files
and use it in the existing signal.c

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewe

linux-user: create a dummy per arch signal.c

Create a signal-common.h for future use by these new files
and use it in the existing signal.c

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20180424192635.6027-2-laurent@vivier.eu>

show more ...