Commit Graph

3961 Commits

Author SHA1 Message Date
Stefan Hajnoczi
7cf6cac151 Merge tag 'linux-user-next-pull-request' of https://github.com/hdeller/qemu-hppa into staging
linux user patches

A series of patches for linux-user, specifically many FPU fixes in signal
handling code for sh4, mips, ppc and s390x (from Matt Turner), a madvise()
improvement (from me), and qemu header cleanups (from Peter Maydell).

---
v3: Fix build failure due to unknown MADV_COLLAPSE constant in madivise() patch
v2: Dropped the "ARM cortex-m55 program loading fix" and the FPU alpha patch

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# gpg: Signature made Fri 29 May 2026 17:51:09 EDT
# gpg:                using EDDSA key BCE9123E1AD29F07C049BBDEF712B510A23A0F5F
# gpg: Good signature from "Helge Deller <deller@gmx.de>" [unknown]
# gpg:                 aka "Helge Deller <deller@kernel.org>" [unknown]
# gpg:                 aka "Helge Deller <deller@debian.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 4544 8228 2CD9 10DB EF3D  25F8 3E5F 3D04 A7A2 4603
#      Subkey fingerprint: BCE9 123E 1AD2 9F07 C049  BBDE F712 B510 A23A 0F5F

* tag 'linux-user-next-pull-request' of https://github.com/hdeller/qemu-hppa:
  linux-user: Move cpu_copy() to user-internals.h
  linux-user: Move init_main_thread() prototype to user-internals.h
  linux-user: Fix typo in function documentation for pgb_addr_set()
  linux-user: Implement finer grained madivse() syscall
  linux-user/s390x: restore fpu_status rounding mode from FPC on sigreturn
  target/sh4: sync fp_status when gdb writes FPSCR
  linux-user/sh4: restore FP rounding mode on sigreturn
  linux-user/sh4: preserve T/M/Q bits across signal delivery
  linux-user/mips: save/restore FCSR across signal delivery
  linux-user/ppc: restore fp_status from FPSCR on sigreturn

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2026-06-01 08:43:13 -04:00
Peter Maydell
07e701716b linux-user: Move cpu_copy() to user-internals.h
We only use cpu_copy() inside linux-user, so we don't need to have
the prototype in qemu.h available to code outside linux-user; move it
to user-internals.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Peter Maydell
9ecb5063c6 linux-user: Move init_main_thread() prototype to user-internals.h
The init_main_thread() prototype is needed only by code internal to
linux-user/, so it doesn't need to be in qemu.h (which is also pulled
in by various files outside linux-user/).

Move the prototype to user-internals.h, and give it a documentation
comment.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Helge Deller
cc39416ec1 linux-user: Fix typo in function documentation for pgb_addr_set()
The third parameter is called guest_hiaddr.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Helge Deller
e519832b25 linux-user: Implement finer grained madivse() syscall
Although most madvise() values are hints, some are important and are
checked by userspace, especially by security-relevant applications like
BoringSLL.  So, return -EINVAL for those functions which we don't emulate.

Signed-off-by: Helge Deller <deller@gmx.de>
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3489
2026-05-29 23:40:53 +02:00
Matt Turner
2762cd51ee linux-user/s390x: restore fpu_status rounding mode from FPC on sigreturn
QEMU keeps the s390x floating-point control register (FPC) in env->fpc.
The rounding mode bits [2:0] of FPC are reflected into the derived
env->fpu_status via set_float_rounding_mode(); every architectural
write to FPC goes through HELPER(sfpc) which keeps the two in sync.

restore_sigregs() restored FPC with a direct assignment:

    __get_user(env->fpc, &sc->fpregs.fpc);

This wrote env->fpc correctly but never updated env->fpu_status, so on
sigreturn the interrupted code resumed with whatever rounding mode the
signal handler last installed in fpu_status.

Factor the two-step "write fpc + sync fpu_status" logic out of
HELPER(sfpc) into cpu_s390x_load_fpc(), declare it in cpu.h, and call
it from restore_sigregs() in place of the direct assignment.

cpu_s390x_load_fpc() partially reuses the sanity check from
HELPER(sfpc): if the FPC value has an invalid rounding mode or reserved
bits set, it falls back to 0, matching the kernel's fpu_lfpc_safe()
behavior where a corrupt signal frame value causes a specification
exception and 0 is used instead.

HELPER(sfpc) now calls cpu_s390x_load_fpc() after its full
specification-exception check, including the FEAT_FLOATING_POINT_EXT
test that is not needed for the signal restore path.

Fixes: 2941e0fa05 ("linux-user/s390x: Save/restore fpc when handling a signal")
Cc: qemu-stable@nongnu.org
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Matt Turner
a740f17ed0 linux-user/sh4: restore FP rounding mode on sigreturn
The SH4 FPSCR rounding-mode (RM) and denormal (DN) bits are not held
only in env->fpscr: they are also reflected into the derived
env->fp_status via set_float_rounding_mode()/set_flush_to_zero(). The
guest keeps the two in sync by routing every write to FPSCR through
helper_ld_fpscr().

restore_sigcontext() wrote the saved value straight into env->fpscr and
never touched env->fp_status, so on sigreturn the interrupted code
resumed with whatever FP rounding mode and flush-to-zero setting the
signal handler last installed. (regs->flags = 0 forces the FR/SZ/PR TB
flags to be recomputed, but fp_status is runtime float state, not a TB
flag, so it was left stale.) This is the FP analogue of the T/M/Q bit
problem just fixed for the integer status register.

Factor the FPSCR -> fp_status synchronisation out of helper_ld_fpscr()
into cpu_load_fpscr() and use it from restore_sigcontext() so the
rounding mode round-trips correctly across signal delivery.

Fixes: c3b5bc8ab3 ("SH4: Signal handling for the user space emulator, by Magnus Damm.")
Cc: qemu-stable@nongnu.org
Reviewed-by: Yoshinori Sato <yoshinori.sato@nifty.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Matt Turner
6bf4c0295c linux-user/sh4: preserve T/M/Q bits across signal delivery
QEMU keeps the SH4 T, M and Q status-register bits outside env->sr, in
the dedicated env->sr_t, env->sr_m and env->sr_q fields; cpu_read_sr()
folds them back into the architectural SR value and cpu_write_sr()
splits them back out.

setup_sigcontext() saved the bare env->sr (so the T/M/Q bits were always
zero in the signal frame) and restore_sigcontext() wrote the value
straight back into env->sr without updating sr_t/sr_m/sr_q. As a result
the T bit was never preserved across signal delivery: on sigreturn the
interrupted code resumed with whatever T value the signal handler last
left behind. Any conditional branch (or addc/subc/rotcl/div1, etc.)
immediately following the interrupted instruction could then take the
wrong path.

This is the cause of the long-standing intermittent failures of the
tests/tcg/multiarch/signals.c test on sh4, which was marked BROKEN. With
a SIGRTMIN timer firing every millisecond across many threads, the race
was hit a few percent of the time and corrupted the guest heap, surfacing
as a SIGSEGV in memset, a malloc assertion, or an rseq registration abort.

Traced on a deterministic rr recording: a cmp/hi set T=0, the timer
signal interrupted the very next instruction (a bf), the handler left
T=1, and the resumed bf took glibc calloc's MORECORE_CLEARS branch,
using the old top-chunk size as the clear length for a freshly split
small chunk and running memset off the end of the heap.

Fix setup_sigcontext()/restore_sigcontext() to use cpu_read_sr() and
cpu_write_sr() so the T, M and Q bits round-trip correctly, and drop the
BROKEN annotation on the sh4 signals test.

Fixes: c3b5bc8ab3 ("SH4: Signal handling for the user space emulator, by Magnus Damm.")
Cc: qemu-stable@nongnu.org
Reviewed-by: Yoshinori Sato <yoshinori.sato@nifty.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Matt Turner
84b920ccb5 linux-user/mips: save/restore FCSR across signal delivery
QEMU keeps the MIPS FPU control/status register (FCSR, fcr31) in
env->active_fpu.fcr31.  The rounding mode, flush-to-zero (FS), and
NaN-2008 mode bits in fcr31 are reflected into the derived
env->active_fpu.fp_status via set_float_rounding_mode() and friends;
every architectural write to FCSR goes through helper_ctc1() which
calls restore_fp_status() to keep the two in sync.

Both target_sigcontext variants (O32 and N32/N64) have an sc_fpc_csr
field that holds FCSR, but setup_sigcontext() never wrote it and
restore_sigcontext() never read it.  As a result:

  - The signal frame always delivered sc_fpc_csr == 0 to the handler,
    so sigaction(SA_SIGINFO) handlers that inspect the interrupted
    context see the wrong FCSR.

  - On sigreturn, active_fpu.fcr31 retained whatever value the signal
    handler last installed (if any), and active_fpu.fp_status was
    never resynced.  Interrupted code resumed with the wrong rounding
    mode, FS flag, and NaN-2008 semantics.

Fix setup_sigcontext() to save fcr31 into sc_fpc_csr.  Fix
restore_sigcontext() to read it back (masked to fcr31_rw_bitmask as
the kernel does) and call cpu_mips_restore_fp_status() to resync
fp_status from the restored fcr31.

Add cpu_mips_restore_fp_status() in target/mips/fpu.c (which already
defines ieee_rm and includes fpu_helper.h), and declare it in cpu.h.

Fixes: 084d0497a0 ("mips-linux-user: Save and restore fpu and dsp from sigcontext")
Cc: qemu-stable@nongnu.org
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Matt Turner
3f50dd4666 linux-user/ppc: restore fp_status from FPSCR on sigreturn
restore_user_regs() restores the PPC FPSCR with a direct assignment:

    env->fpscr = (uint32_t) fpscr;

ppc_store_fpscr() exists precisely to write FPSCR and keep the derived
env->fp_status in sync: it calls fpscr_set_rounding_mode() to update
the softfloat rounding mode, and set_float_rebias_overflow/underflow()
to reflect the FP_OE/FP_UE enable bits.  The direct assignment bypasses
all of this.

On sigreturn, interrupted code resumes with whatever rounding mode and
overflow/underflow-rebias state the signal handler last installed in
fp_status, rather than the state that was saved at signal delivery.

Replace the direct assign with ppc_store_fpscr().  The FPSCR_MTFS_MASK
applied inside ppc_store_fpscr() only excludes the computed FP_FEX and
FP_VX bits, which it re-derives correctly from the exception and enable
bits in the restored value.

Fixes: bcd4933a23 ("linux-user: ppc signal handling")
Cc: qemu-stable@nongnu.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-29 23:40:53 +02:00
Richard Henderson
5e18eaab88 target/arm: Enable FEAT_CMPBR for -cpu max
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260518174750.660258-5-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-05-28 15:06:23 +01:00
Stefan Hajnoczi
3f89b5de5b Merge tag 'pull-target-arm-20260526' of https://gitlab.com/pm215/qemu into staging
target-arm queue:
 * hw/timer/mss_timer: Remove dead code in timer_write()
 * OMAP: Remove various pieces of dead code
 * target/arm: Set debug in attrs in translate_for_debug()
 * target/arm/ptw: Flip sense of get_phys_addr_* return values
 * tests/functional/aarch64: Bump up timeout on vbsa
 * target/arm: Fix minor FEAT_AFP corner case bugs
 * target/arm: Implement FEAT_FAMINMAX
 * target/arm: Implement FEAT_FPMR
 * target/arm: Some initial patches towards other FP8 features

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# gpg: Signature made Tue 26 May 2026 10:27:35 EDT
# gpg:                using RSA key E1A5C593CD419DE28E8315CF3C2525ED14360CDE
# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [full]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [full]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [full]
# gpg:                 aka "Peter Maydell <peter@archaic.org.uk>" [unknown]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* tag 'pull-target-arm-20260526' of https://gitlab.com/pm215/qemu: (54 commits)
  target/arm: Move vectors_overlap to vec_internal.h
  target/arm: Split vector-type.h from cpu.h
  target/arm: Implement FSCALE for SME
  target/arm: Implement FSCALE for AdvSIMD
  target/arm: Add isar_feature_aa64_f8cvt
  target/arm: Implement ID_AA64FPFR0
  target/arm: Enable FEAT_FPMR for -cpu max
  linux-user/aarch64: Implement FPMR signal frames
  target/arm: Dump FPMR when present
  tests/functional/aarch64/rme: update images to support FEAT_FP8
  target/arm: Trap direct acceses to FPMR
  target/arm: Add FPMR_EL to TBFLAGS
  target/arm: Clear FPMR on ResetSVEState
  target/arm: Enable EnFPM bits for FEAT_FPMR
  target/arm: Update SCTLR bits for FEAT_FPMR
  target/arm: Introduce FPMR
  target/arm: Update HCRX bits for Arm ARM M.a.a
  target/arm: Update SCR bits for Arm ARM M.a.a
  target/arm: Enable FEAT_FAMINMAX for -cpu max
  target/arm: Implement FEAT_FAMINMAX for SVE
  ...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2026-05-26 13:20:15 -04:00
Richard Henderson
2430d49a17 target/arm: Enable FEAT_FPMR for -cpu max
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260522220306.235200-18-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-05-26 11:41:00 +01:00
Richard Henderson
82e6411eac linux-user/aarch64: Implement FPMR signal frames
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260522220306.235200-17-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-05-26 11:41:00 +01:00
Richard Henderson
697910f67f target/arm: Enable FEAT_FAMINMAX for -cpu max
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20260522220306.235200-6-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-05-26 11:41:00 +01:00
Matt Turner
975bd51a88 linux-user/sh4: add VDSO support for sh4 and sh4eb
Provides replacement VDSO with sigreturn trampolines
(__kernel_sigreturn, __kernel_rt_sigreturn) and syscall stubs
(clock_gettime, clock_gettime64, clock_getres, gettimeofday).

Both LE and BE blobs are committed and selected at compile time via
TARGET_BIG_ENDIAN. The BE variant requires an sh4eb-unknown-linux-gnu
toolchain; sh4-unknown-linux-gnu does not support -mb.

CFI register numbers follow GCC's SH_DEBUGGER_REGNO:
PR=17, GBR=18, MACH=20, MACL=21, FPUL=23, FPSCR=24, FR0-15=25-40.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
Matt Turner
4b5e20839b linux-user/riscv: add coredump support
Define HAVE_ELF_CORE_DUMP and target_elf_gregset_t in target_elf.h,
mirroring struct user_regs_struct: pc followed by x1 (ra) through
x31 (t6).  Implement elf_core_copy_regs() in elfload.c to populate
the gregset from CPURISCVState.

Without this, bprm->core_dump is NULL for RISC-V targets.  When a
guest signal goes unhandled, dump_core_and_abort() skips the core
write and falls through to die_with_signal(), which re-raises the
signal to the host.  The host kernel then writes an x86-64 core file
for the qemu-riscv64 process instead of a RISC-V guest core.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
Matt Turner
75b5f03310 linux-user/mips: use tswap32 in elf_core_copy_regs
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
Matt Turner
6033df08e9 linux-user/mips64: fix mipsn32 elf_core_copy_regs entry width
For mipsn32 (TARGET_ABI32=y, TARGET_LONG_BITS=64):
  abi_ulong = uint32_t (4 bytes) — for pointers and ABI-sized fields
  target_ulong = uint64_t (8 bytes) — for general-purpose registers

linux-user/elfload.c allocates target_elf_prstatus using the
mips64/target_elf.h definition where target_elf_gregset_t has
target_ulong reserved[45] (8 bytes each, 360 bytes total).

However, in linux-user/mips64/elfload.c, #include "target_elf.h" inside
the included mips/elfload.c resolves to mips/target_elf.h (compiler
searches the file's own directory first), where the union uses abi_ulong
reserved[45].  For mipsn32 this gives 4-byte entries (180 bytes), not
the 8-byte entries (360 bytes) that elfload.c actually allocated.

Writing via r->reserved[34] therefore lands at byte offset 34*4=136
instead of the correct 34*8=272, silently zeroing the EPC in the core
file.

Fix by casting the pointer to target_ulong * so writes always use 8-byte
slots and land at the offsets matching the allocated layout.

This does not change behavior for mips64 (N64) where abi_ulong already
equals target_ulong (both 8 bytes).

Signed-off-by: Matt Turner <mattst88@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
Matt Turner
dd3a906d35 linux-user/mips64: fix elf_core_copy_regs register layout in core files
mips64/elfload.c uses #include "../mips/elfload.c" to share code. When
the compiler processes mips/elfload.c the quoted #include "target_elf.h"
resolves relative to the including file's directory, so it picks up
mips/target_elf.h instead of mips64/target_elf.h.  mips/target_elf.h
pulls in mips/target_ptrace.h, whose target_pt_regs has a pad0[6] field
before regs[].  As a result elf_core_copy_regs writes:

  r->pt.regs[i]   -> reserved[6+i]   (shifted by 6 from the correct index)
  r->pt.cp0_epc   -> reserved[40]    (correct mips64 N64 index is 34)

The Linux kernel and glibc both use the mips64 N64 layout (no pad0): EPC
at reserved[34].  Debuggers and libunwind reading the core with N64
constants therefore see a completely wrong register set — EPC points to
GP, RA holds the branch target instead of the link address, etc.

Fix by:
 - Guarding the mips32 elf_core_copy_regs in mips/elfload.c with #ifndef
   TARGET_MIPS64 so it is not compiled for mips64/mipsn32 targets.
 - Providing a mips64-specific elf_core_copy_regs in mips64/elfload.c
   that writes directly to r->reserved[i] with the correct N64 indices,
   bypassing the struct field names that are tainted by the wrong header
   include.

The mipsn32 (TARGET_ABI_MIPSN32) and mips64el targets are covered by the
same mips64/elfload.c and benefit from the same fix.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
Matt Turner
1645c2e028 linux-user/hppa: add coredump support
Add HAVE_ELF_CORE_DUMP, target_elf_gregset_t (80 entries matching
arch/parisc/include/uapi/asm/ptrace.h), and elf_core_copy_regs().

The struct layout matches the kernel's struct user_regs_struct:
  gr[0..31]    at indices [0..31]   (PSW in gr[0])
  sr[0..7]     at indices [32..39]
  iaoq[0..1]   at indices [40..41]  (instruction address queue)
  iasq[0..1]   at indices [42..43]
  sar          at index   [44]      (shift amount / CR11)
  iir          at index   [45]      (interrupt instruction register)
  isr          at index   [46]      (interrupt space register)
  ior          at index   [47]      (interrupt offset register)
  ipsw         at index   [48]      (interrupt PSW / CR22)
  cr0          at index   [49]      (recovery counter)
  cr24_31[8]   at indices [50..57]
  cr8_15[6]    at indices [58..63]
  pad[16]      at indices [64..79]

elf_core_copy_regs() saves GRs, IAOQ (front/back), and SAR.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-24 15:07:28 +02:00
James Hilliard
bd8820aa7b linux-user/mips, target/mips: honor MIPS_FIXADE for unaligned accesses
Linux/MIPS enables software fixups for user-mode unaligned scalar
accesses by default through MIPS_FIXADE/TIF_FIXADE.  QEMU linux-user did
not model that ABI, so MIPS guests took fatal AdEL/AdES exceptions unless
translation was forced to use unaligned host accesses.

Key MIPS translation blocks on the linux-user unaligned policy, implement
sysmips(MIPS_FIXADE) to toggle that policy, and raise SIGBUS/BUS_ADRALN
when fixups are disabled.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20260520172313.23777-4-philmd@linaro.org>
2026-05-21 08:20:58 +02:00
James Hilliard
5c6f4d7054 linux-user/mips: implement sysmips(MIPS_ATOMIC_SET)
Implement the MIPS_ATOMIC_SET sysmips command as an aligned 32-bit atomic
exchange in target memory.

MIPS reports syscall errors through a separate register, so successful old
values can overlap the errno range.  Write the return value and error flag
directly and return -QEMU_ESIGRETURN so the common syscall path leaves the
registers unchanged.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20260520172313.23777-3-philmd@linaro.org>
2026-05-21 08:20:58 +02:00
James Hilliard
e83a42cbf7 linux-user/mips: implement sysmips(MIPS_FLUSH_CACHE)
Add the target sysmips dispatcher and implement MIPS_FLUSH_CACHE as a
successful no-op for linux-user.

Self-modifying code is handled by QEMU's normal user-mode translation
invalidation machinery, so the target ABI only needs the syscall command
to be accepted.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20260520172313.23777-2-philmd@linaro.org>
2026-05-21 08:20:58 +02:00
Philippe Mathieu-Daudé
586663f1fa buildsys: Remove MIPS TCG backend
We removed support for MIPS host. Remove the now unreachable
TCG host code.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20260511135312.38705-6-philmd@linaro.org>
2026-05-21 08:20:58 +02:00
Warner Losh
1e000f9671 linux-user: Fix a memory leak when pthread_create fails
Fix one of the TODO items when creating a new thread: release the copied
cpu and free the task state.

Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-19 15:49:35 +02:00
Matt Turner
9ac5aa7227 linux-user/sh4: Fix setup_sigtramp to match Linux kernel trampoline pattern
QEMU used MOVW(2) (0x9300), which loads the syscall number from PC+4,
instead of the kernel's MOVW(7) (0x9305), which loads from PC+14.  The
kernel uses five "or r0,r0" nop pads between TRAP_NOARG and the syscall
number word to reach that offset.  libunwind's unw_is_signal_frame checks
for the exact kernel byte pattern 0xc3109305 at the frame PC, so QEMU's
compact layout was not detected, breaking unwinding through signal frames.

Expand each trampoline from 6 to 16 bytes matching the kernel layout
defined in arch/sh/kernel/signal_32.c:

  #define MOVW(n)    (0x9300|((n)-2))  /* Move mem word at PC+n to R3 */
  #define TRAP_NOARG 0xc310            /* Syscall w/no args (NR in R3) */
  #define OR_R0_R0   0x200b            /* or r0,r0 (insert to avoid hardware bug) */

  __put_user(MOVW(7),          &frame->retcode[0]);  /* 0x9305 */
  __put_user(TRAP_NOARG,       &frame->retcode[1]);  /* 0xc310 */
  __put_user(OR_R0_R0,         &frame->retcode[2]);  /* 0x200b */
  __put_user(OR_R0_R0,         &frame->retcode[3]);  /* 0x200b */
  __put_user(OR_R0_R0,         &frame->retcode[4]);  /* 0x200b */
  __put_user(OR_R0_R0,         &frame->retcode[5]);  /* 0x200b */
  __put_user(OR_R0_R0,         &frame->retcode[6]);  /* 0x200b */
  __put_user((__NR_sigreturn), &frame->retcode[7]);

The first two halfwords (MOVW(7) || TRAP_NOARG = 0xc3109305) form the
32-bit value libunwind checks at the frame PC, followed by two
OR_R0_R0 halfwords (0x200b200b) at PC+4.  The same layout applies to
the rt_sigreturn trampoline (lines 366-373 of signal_32.c).

Neither this fix nor the companion tuc_link fix is independently
sufficient: this fix makes signal frames detectable but register reads
remain garbage without the correct ucontext layout; that fix corrects the
ucontext layout but libunwind still cannot detect the frame without the
correct trampoline pattern.  Together they fix the following libunwind
tests on a 64-bit host:
  Gtest-sig-context, Gtest-trace, Ltest-init-local-signal,
  Ltest-sig-context, Ltest-trace

Signed-off-by: Matt Turner <mattst88@gmail.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-19 15:40:38 +02:00
Matt Turner
c3176e6457 linux-user/sh4: Fix target_ucontext tuc_link field type
tuc_link is declared as 'struct target_ucontext *', which is a HOST
pointer.  On a 64-bit host running a 32-bit SH4 target, this is 8 bytes
instead of the 4 bytes the target expects, padding pushes tuc_mcontext
8 bytes past its correct offset.

When a signal handler receives ucontext_t *, every field accessed through
uc_mcontext (gregs[], pc, pr, ...) is read from the wrong address.  In
particular the saved PC comes back as a garbage stack value, which breaks
any code that initialises a libunwind cursor from the signal context.

Fix it by using abi_ulong, which is always sized to the target ABI (4
bytes for SH4), matching the layout the kernel and glibc agree on.  This
is the same pattern used by arm/signal.c.

Also remove the (unsigned long *) cast from the __put_user that zeros
tuc_link.  The cast was harmless when tuc_link was pointer-sized (8
bytes matching unsigned long on a 64-bit host), but after the type
change __put_user's sizeof dispatch would select stq_le_p (8-byte write)
for a now-4-byte field, silently overwriting the start of tuc_stack.

Neither this fix nor the companion setup_sigtramp fix is independently
sufficient: this fix corrects register values read from the signal context
but libunwind still cannot detect the frame without the correct trampoline
pattern; that fix makes the frame detectable but register reads remain
garbage without the correct ucontext layout.  Together they fix the
following libunwind tests on a 64-bit host:
  Gtest-sig-context, Gtest-trace, Ltest-init-local-signal,
  Ltest-sig-context, Ltest-trace

Signed-off-by: Matt Turner <mattst88@gmail.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-19 15:40:38 +02:00
Helge Deller
6b5aef7cac linux-user: Fix AT_EXECFN in AUXV for symlinked programs
The AT_EXECFN entry in AUXV needs to keep the value which was used when
the program was started. Especially for symlinked programs qemu should
not try to resolve the realpath.

Here is a reproducer:
(arm64-chroot)root@p100:/# cd /usr/bin
(arm64-chroot)root@p100:/usr/bin# ln -s echo testprog
(arm64-chroot)root@p100:/usr/bin# LD_SHOW_AUXV=1 ./testprog | grep AT_EXECFN
AT_EXECFN:            ./testprog

In this example, "./testprog" is the correct output, and not "/usr/bin/echo".

This patch fixes parts of commit 258bec39 ("linux-user: Fix access to
/proc/self/exe").

Fixes: 258bec39 ("linux-user: Fix access to /proc/self/exe")
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3379
Signed-off-by: Helge Deller <deller@gmx.de>
2026-05-19 15:37:33 +02:00
Richard Henderson
9e25e249c7 linux-user/arm: Restrict regpairs_aligned
The function regpairs_aligned is for extracting a 64-bit
quantity from a pair of 32-bit registers and does not
apply to AArch64.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20260409035015.132370-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-05-05 09:25:21 +01:00
Helge Deller
9667bf3249 linux-user: Translate errno in IP_RECVERR and IPV6_RECVERR
Translate host error codes of IP_RECVERR and IPV6_RECVERR control messages to
target error codes before returning to the caller.
For example, this is important for architectures (e.g. hppa, alpha, sparc,
mips) on which the value of ECONNREFUSED is different to the value on a x86_64
host.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/602
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-30 09:00:04 +02:00
Helge Deller
08dc3e240f linux-user: Allow getsockopt() with NULL optval address
Some programs test availability of socket options by asking for the
value with an NULL optval address, which currenrly always trigger an
EFAULT in qemu.  Fix it by allowing a NULL address, in the same manner
as the Linux kernel on physical machines.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/2390
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@oss.qualcomm.com>
2026-04-30 09:00:04 +02:00
Helge Deller
9fb681792d linux-user: Flush errors by using exit() instead of _exit() in error path
Similiar to previous patch - ensure that we always flush I/O by using
exit() instead of _exit().

Reported by: Tobias Bergkvist <tobias@bergkv.ist>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/2544
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-28 22:16:51 +02:00
Helge Deller
dcb6e96257 linux-user: Add missing CDROM ioctls
Add the missing CDROM ioctls and bring them in same order as
documentation.

Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-28 22:16:51 +02:00
Stefan Hajnoczi
759c456b1d Merge tag 'linux-user-next-pull-request' of https://github.com/hdeller/qemu-hppa into staging
linux-user: Pull request

This patch series adds myself as linux-user maintainer, and includes some
patches which have piled up for linux-user during the last few weeks.

Please apply.
Thanks!
Helge

* tag 'linux-user-next-pull-request' of https://github.com/hdeller/qemu-hppa:
  linux-user: Flush errors by using exit() instead of _exit() in error path
  linux-user: Use abi_int for imr_ifindex in ip_mreqn struct
  linux-user: Fix CLONE_PARENT_SETTID when using fork-like clone
  linux-user: Add getsockopt() for SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW
  linux-user: Add setsockopt() for SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW
  linux-user: Define SO_TIMESTAMP*_NEW and SO_RCVTIMEIO_NEW
  linux-user/mips: sync k0 TLS for EF_MIPS_MACH_OCTEON userlands
  linux-user/strace: Use pointer type for read and write values
  linux-user/arm/nwfpe: Use thread-local storage for qemufpa
  linux-user/arm/nwfpe: Replace user_registers with current_cpu
  linux-user: Don't define target_stat64 struct for loongarch64
  linux-user: fix off-by-one in host_to_target_for_each_rtattr()
  linux-user/ppc: Fix ppc64 rt_sigframe stack offset
  MAINTAINERS: Add myself as maintainer for linux-user

[I have confirmed with Laurent, the current maintainer, that he would
like Helge to help.
-- Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Conflicts:
  MAINTAINERS
  Pierrick's email address changed.
2026-04-27 12:57:33 -04:00
Helge Deller
9e7734ead1 linux-user: Flush errors by using exit() instead of _exit() in error path
Qemu user mode does not properly flushes error messages related to bad
arguments when exiting (at least when the output is piped to a file
instead of running on a terminal).
Ensure that we always flush by using exit() instead of _exit().

Reported by: Tobias Bergkvist
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/2544
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 16:38:39 +02:00
Helge Deller
e2af3eadc0 linux-user: Use abi_int for imr_ifindex in ip_mreqn struct
Peter Hartley noticed, that in the qemu code the imr_ifindex member of
struct target_ip_mreq needs to be of type "int" instead of "long", which
is what the Linux kernel uses on all architectures.

Adjust the type accordingly, and add a QEMU_BUILD_BUG_ON() checker to
prevent such issues in the future.

This change should fix multicast issues when using hosts and guests with
different endianess or bit size.

Reported-by: Peter Hartley <peter@talesfromthearmchair.net>
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/2553
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:33 +02:00
Helge Deller
b03a6ac6fa linux-user: Fix CLONE_PARENT_SETTID when using fork-like clone
The CLONE_PARENT_SETTID option requires the implementation to store the
child thread ID at the location pointed to by parent_tid in the parent's
memory.

Fix our implementation and move the code from the client side (where
fork returned 0), to the parent side and store the return value from the
fork call (which is the client TID) in the parent_tid pointer.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3340
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2026-04-25 00:38:32 +02:00
Helge Deller
07c7decaa5 linux-user: Add getsockopt() for SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW
Add handlers for both sockopts which use 64-bit time_t from userspace.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/885
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Helge Deller
edb4588309 linux-user: Add setsockopt() for SO_RCVTIMEO_NEW and SO_SNDTIMEO_NEW
Add handlers for both sockopts which use 64-bit time_t from userspace.

Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/885
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Helge Deller
8b60ed8354 linux-user: Define SO_TIMESTAMP*_NEW and SO_RCVTIMEIO_NEW
Define the entries which always use the 64-bit timestamps.

Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
James Hilliard
4c681ba3b8 linux-user/mips: sync k0 TLS for EF_MIPS_MACH_OCTEON userlands
Cavium Octeon userspace is not following a generic MIPS Linux TLS
ABI rule here. Older Octeon glibc uses the k0 register as the fast
thread pointer, while newer Octeon2 and Octeon3 glibc variants use
the normal rdhwr $29 path.

linux-user already updates CP0_UserLocal for cpu_set_tls() and
TARGET_NR_set_thread_area, but it does not keep gpr[26]
synchronized. That leaves EF_MIPS_MACH_OCTEON userlands able to
complete set_thread_area() and still reach pthread startup or
pthread_self() with a stale k0 value.

Use the existing MIPS ELF machine flags from linux-user/elfload.c and
mirror CP0_UserLocal into gpr[26] only for EF_MIPS_MACH_OCTEON.

Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Alistair Francis
1730e6f33f linux-user/strace: Use pointer type for read and write values
The stack pointer is being truncated as 32-bits for qemu-riscv64, so
let's use %p to print the syscall pointer argument.

Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/work_items/3238
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Nutty Liu <nutty.liu@hotmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Richard Henderson
784f1dde90 linux-user/arm/nwfpe: Use thread-local storage for qemufpa
Fix the thread safety of the emulation by not storing a
pointer in global storage.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Richard Henderson
c8ea175900 linux-user/arm/nwfpe: Replace user_registers with current_cpu
Use the thread-local variable current_cpu instead of
a global variable to access the general registers.
This also means we don't need to pass env to EmulateAll.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Gyorgy Tamasi
93484c768f linux-user: Don't define target_stat64 struct for loongarch64
The kernel defines 'struct stat64' only if
__BITS_PER_LONG != 64 || defined(__ARCH_WANT_STAT64).
loongarch64 doesn't set __ARCH_WANT_STAT64, and it isn't 32-bit,
so it won't get this struct.

QEMU incorrectly does define a target_stat64 struct. However this
isn't causing any guest-visible problems, because defining the
target_stat64 struct and TARGET_HAS_STRUCT_STAT64 affects these
syscalls:
 TARGET_NR_stat64
 TARGET_NR_lstat64
 TARGET_NR_fstat64
 TARGET_NR_fstatat64
 TARGET_NR_newfstatat

For loongarch64 the only one of those we provide is newfstatat,
and that is actually a separate QEMU bug, because the kernel does
not provide that syscall for this architecture. No real guest
code will be using a syscall that doesn't exist in the ABI.

(Some of these syscalls are present in the loongarch64 "ABI1.0",
but that ABI was never accepted in the upstream kernel, and
QEMU does not model that ABI, only the "ABI2.0".)

Stop defining TARGET_HAS_STRUCT_STAT64 anyway, for consistency
with the kernel and to avoid confusion.

Note:
Commit message suggested by Peter Maydell <peter.maydell@linaro.org>

Signed-off-by: Gyorgy Tamasi <gyorgy.tamasi@gmail.com>
Tested-by: Gyorgy Tamasi <gyorgy.tamasi@gmail.com>
Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
2026-04-25 00:38:32 +02:00
Yixin Wei
029f10e852 linux-user: fix off-by-one in host_to_target_for_each_rtattr()
host_to_target_for_each_rtattr() uses "len > sizeof(struct rtattr)"
as its loop condition. When the last rtattr in a netlink message has
exactly sizeof(struct rtattr) (4) bytes remaining, the loop exits
without byte-swapping its rta_len and rta_type. A big-endian guest
then reads rta_len in the wrong byte order and fails validation.

The companion function target_to_host_for_each_rtattr() correctly
uses ">=" (added in commit fa2229dbf8). The kernel's RTA_OK macro
also uses ">=". Fix the host_to_target direction to match.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2485
Signed-off-by: Yixin Wei <yixinwei@meta.com>
Fixes: 6c5b5645ae ("linux-user: add rtnetlink(7) support")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: qemu-stable@nongnu.org
2026-04-25 00:38:32 +02:00
Matt Turner
654dce6c52 linux-user/ppc: Fix ppc64 rt_sigframe stack offset
The kernel's 64-bit signal delivery (signal_64.c) uses:

    newsp = frame - __SIGNAL_FRAMESIZE

while the 32-bit path (signal_32.c) uses:

    newsp = frame - (__SIGNAL_FRAMESIZE + 16)

The extra 16 bytes in the 32-bit case is to place siginfo and ucontext
at the same offsets as older kernels (see the comment in signal_32.c).
The 64-bit rt_sigframe starts with ucontext directly and does not need
this adjustment.

QEMU's setup_rt_frame() unconditionally used (SIGNAL_FRAMESIZE + 16)
for both 32-bit and 64-bit, placing the handler's SP 16 bytes too low
on ppc64. Signal delivery and return still worked because do_rt_sigreturn
had the matching wrong offset, but the vDSO DWARF unwind info encodes
the correct kernel offset. This caused any DWARF unwinder (libunwind,
libgcc, etc.) to compute a CFA that is 16 bytes off, reading garbage
register values from the signal frame.

Define RT_SIGFRAME_ADJUST (0 on ppc64, 16 on ppc32) and use it in both
setup_rt_frame and do_rt_sigreturn to match the kernel.

This was verified by A/B testing with libunwind's test suite:

  ppc64le: Gtest-bt, Ltest-bt, Gtest-concurrent, Ltest-concurrent,
           and Ltest-sig-context all change from FAIL to PASS.
  ppc64be: Gtest-bt, Ltest-bt, and Ltest-sig-context all change
           from FAIL to PASS.

Signed-off-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: qemu-stable@nongnu.org
2026-04-25 00:38:32 +02:00
Taylor Simpson
910ce4de83 Hexagon (linux-user/hexagon) Identify Hexagon version in ELF file
Return proper Hexagon CPU version from get_elf_cpu_model

Co-authored-by: Matheus Tavares Bernardino <matheus.bernardino@oss.qualcomm.com>
Co-authored-by: Brian Cain <brian.cain@oss.qualcomm.com>
Signed-off-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Brian Cain <brian.cain@oss.qualcomm.com>
2026-04-23 14:49:38 -07:00
Nicholas Piggin
7e966ef38f bsd-user, linux-user: signal: recursive signal delivery fix
Synchronous signals must accommodate a synchronous signal being
raised during delivery, as asynchronous ones do. For example
badframe errors during delivery will cause SIGSEGV to be raised.

Without this fix, cpu_loop() runs process_pending_signals() which
delivers the first synchronous signal (e.g., SIGILL) which fails
to set the handler and forces SIGSEGV, but that is not picked up.
process_pending_signals() returns. Then cpu_loop() runs cpu_exec()
again, which attempts to execute the same instruction, another
SIGILL.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20260321135624.581398-3-npiggin@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2026-03-31 19:13:20 +01:00