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>
The feature test functions isar_feature_*() now take up nearly
a thousand lines in target/arm/cpu.h. This header file is included
by a lot of source files, most of which don't need these functions.
Move the feature test functions to their own header file.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20231024163510.2972081-2-peter.maydell@linaro.org
The oldest supported cpu is the microsparc 1; all other cpus
use CPU_DEFAULT_FEATURES. Remove the features that must always
be present for sparcv7: FLOAT, SWAP, FLUSH, FSQRT, FMUL.
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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>
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>
Make host_signal_handler slightly easier to read.
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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>
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>
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>
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>
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>
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>
Do not assert success, but return any failure received.
Additionally, fix the method of earlier error return in target_munmap.
Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Since support for LSX and LASX is landed in QEMU recently, we can update
HWCAPS accordingly.
Signed-off-by: Jiajie Chen <c@jia.je>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231001085315.1692667-1-c@jia.je>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
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>
QEMU mips userspace emulation crashes with "qemu: unhandled CPU exception
0x15 - aborting" when one of the integer arithmetic instructions detects
an overflow.
This patch fixes it so that it delivers SIGFPE with FPE_INTOVF instead.
Cc: qemu-stable@nongnu.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Message-Id: <3ef979a8-3ee1-eb2d-71f7-d788ff88dd11@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The previous change, 2d385be615, assumed !PAGE_VALID meant that
the page would be unmapped by the elf image. However, since we
reserved the entire image space via mmap, PAGE_VALID will always
be set. Instead, assume PROT_NONE for the same condition.
Furthermore, assume bss is only ever present for writable segments,
and that there is no page overlap between PT_LOAD segments.
Instead of an assert, return false to indicate failure.
Cc: qemu-stable@nongnu.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1854
Fixes: 2d385be615 ("linux-user: Do not adjust zero_bss for host page size")
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
p is a generic variable in syscall() and can be used by any syscall
case, so this patch removes the useless local variable declaration for
the following syscalls: TARGET_NR_llistxattr, TARGET_NR_listxattr,
TARGET_NR_setxattr, TARGET_NR_lsetxattr, TARGET_NR_getxattr,
TARGET_NR_lgetxattr, TARGET_NR_removexattr, TARGET_NR_lremovexattr.
Fix following warnings:
.../linux-user/syscall.c:12342:15: warning: declaration of 'p' shadows a previous local [-Wshadow=compatible-local]
12342 | void *p, *b = 0;
| ^
.../linux-user/syscall.c:8975:11: note: shadowed declaration is here
8975 | void *p;
| ^
.../linux-user/syscall.c:12379:19: warning: declaration of 'p' shadows a previous local [-Wshadow=compatible-local]
12379 | void *p, *n, *v = 0;
| ^
.../linux-user/syscall.c:8975:11: note: shadowed declaration is here
8975 | void *p;
| ^
.../linux-user/syscall.c:12424:19: warning: declaration of 'p' shadows a previous local [-Wshadow=compatible-local]
12424 | void *p, *n, *v = 0;
| ^
.../linux-user/syscall.c:8975:11: note: shadowed declaration is here
8975 | void *p;
| ^
.../linux-user/syscall.c:12469:19: warning: declaration of 'p' shadows a previous local [-Wshadow=compatible-local]
12469 | void *p, *n;
| ^
.../linux-user/syscall.c:8975:11: note: shadowed declaration is here
8975 | void *p;
| ^
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20230925151029.461358-6-laurent@vivier.eu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Fix following warnings:
.../linux-user/mmap.c: In function 'target_mremap':
.../linux-user/mmap.c:913:13: warning: declaration of 'prot' shadows a previous local [-Wshadow=compatible-local]
913 | int prot = 0;
| ^~~~
../../../Projects/qemu/linux-user/mmap.c:871:9: note: shadowed declaration is here
871 | int prot;
| ^~~~
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20230925151029.461358-3-laurent@vivier.eu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Fix following warnings:
.../linux-user/flatload.c: In function 'load_flt_binary':
.../linux-user/flatload.c:758:23: warning: declaration of 'p' shadows a previous local [-Wshadow=compatible-local]
758 | abi_ulong p;
| ^
../../../Projects/qemu/linux-user/flatload.c:722:15: note: shadowed declaration is here
722 | abi_ulong p;
| ^
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-ID: <20230925151029.461358-2-laurent@vivier.eu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
Use abi_ullong not uint64_t so that the alignment of the field
and therefore the layout of the struct is correct.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The tcg/tcg.h header is a big bucket, containing stuff related to
the translators and the JIT backend. The places that initialize
tcg or create new threads do not need all of that, so split out
these three functions to a new header.
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We can load tcg_ctx just as easily within the callee.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Fix:
linux-user/strace.c: In function ‘print_sockaddr’:
linux-user/strace.c:370:17: warning: declaration of ‘i’ shadows a previous local [-Wshadow=compatible-local]
370 | int i;
| ^
linux-user/strace.c:361:9: note: shadowed declaration is here
361 | int i;
| ^
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230904161235.84651-20-philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Enable FEAT_MOPS on the AArch64 'max' CPU, and add it to
the list of features we implement.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230912140434.1333369-13-peter.maydell@linaro.org
FEAT_HBC (Hinted conditional branches) provides a new instruction
BC.cond, which behaves exactly like the existing B.cond except
that it provides a hint to the branch predictor about the
likely behaviour of the branch.
Since QEMU does not implement branch prediction, we can treat
this identically to B.cond.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Add the code to report the arm32 hwcaps we were previously missing:
ss, ssbs, fphp, asimdhp, asimddp, asimdfhm, asimdbf16, i8mm
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Our lists of Arm 32 and 64 bit hwcap values have lagged behind
the Linux kernel. Update them to include all the bits defined
as of upstream Linux git commit a48fa7efaf1161c1 (in the middle
of the kernel 6.6 dev cycle).
For 64-bit, we don't yet implement any of the features reported via
these hwcap bits. For 32-bit we do in fact already implement them
all; we'll add the code to set them in a subsequent commit.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Some of the names we use for CPU features in linux-user's dummy
/proc/cpuinfo don't match the strings in the real kernel in
arch/arm64/kernel/cpuinfo.c. Specifically, the SME related
features have an underscore in the HWCAP_FOO define name,
but (like the SVE ones) they do not have an underscore in the
string in cpuinfo. Correct the errors.
Fixes: a55b9e7226 ("linux-user: Emulate /proc/cpuinfo on aarch64 and arm")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230914022645.1151356-12-gaosong@loongson.cn>
The code in setup_rt_frame reads two words at haddr, but locks only one.
This patch fixes it to lock both.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
qemu-hppa may crash when delivering a signal. It can be demonstrated with
this program. Compile the program with "hppa-linux-gnu-gcc -O2 signal.c"
and run it with "qemu-hppa -one-insn-per-tb a.out". It reports that the
address of the flag is 0xb4 and it crashes when attempting to touch it.
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <signal.h>
sig_atomic_t flag;
void sig(int n)
{
printf("&flag: %p\n", &flag);
flag = 1;
}
int main(void)
{
struct sigaction sa;
struct itimerval it;
sa.sa_handler = sig;
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
if (sigaction(SIGALRM, &sa, NULL)) perror("sigaction"), exit(1);
it.it_interval.tv_sec = 0;
it.it_interval.tv_usec = 100;
it.it_value.tv_sec = it.it_interval.tv_sec;
it.it_value.tv_usec = it.it_interval.tv_usec;
if (setitimer(ITIMER_REAL, &it, NULL)) perror("setitimer"), exit(1);
while (1) {
}
}
The reason for the crash is that the signal handling routine doesn't clear
the 'N' flag in the PSW. If the signal interrupts a thread when the 'N'
flag is set, the flag remains set at the beginning of the signal handler
and the first instruction of the signal handler is skipped.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
This patch adds the new extensions in
linux 6.5 to the hwprobe syscall.
And fixes RVC check to OR with correct value.
The previous variable contains 0 therefore it
did work.
Signed-off-by: Robbin Ehn <rehn@rivosinc.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Message-ID: <bc82203b72d7efb30f1b4a8f9eb3d94699799dc8.camel@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
We should not use types dependend on host arch for target_ucontext.
This bug is found when run rv32 applications.
Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20230811055438.1945-1-zhiwei_liu@linux.alibaba.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Remove the fixed size shm_regions[] array.
Remove references when other mappings completely remove
or replace a region.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If the shm region is not mapped at shmaddr, EINVAL.
Do not unmap the region until the syscall succeeds.
Use mmap_reserve_or_unmap to preserve reserved_va semantics.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Rename from do_* to target_*. Fix some minor checkpatch errors.
Tested-by: Helge Deller <deller@gmx.de>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Warner Losh <imp@bsdimp.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The start_mmap value is write-only.
Remove the field and the defines that populated it.
Logically, this has been replaced by task_unmapped_base.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Core dumps produced by gdb's gcore when connected to qemu's gdbstub
lack stack. The reason is that gdb includes only anonymous memory in
core dumps, which is distinguished by a non-0 Anonymous: value.
Consider the mappings with PAGE_ANON fully anonymous, and the mappings
without it fully non-anonymous.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
[rth: Update for open_self_maps_* rewrite]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
PIE executables are usually linked at offset 0 and are
relocated somewhere during load. The hiaddr needs to
be adjusted to keep the brk next to the executable.
Cc: qemu-stable@nongnu.org
Fixes: 1f356e8c01 ("linux-user: Adjust initial brk when interpreter is close to executable")
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Replace the by-hand method of region identification with
the official user-exec interface. Cross-check the region
provided to the callback with the interval tree from
read_self_maps().
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use dev_t instead of a string, and ino_t instead of uint64_t.
The latter is likely to be identical on modern systems but is
more type-correct for usage.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add emulation for /proc/cpuinfo for the alpha architecture.
alpha output example:
(alpha-chroot)root@p100:/# cat /proc/cpuinfo
cpu : Alpha
cpu model : ev67
cpu variation : 0
cpu revision : 0
cpu serial number : JA00000000
system type : QEMU
system variation : QEMU_v8.0.92
system revision : 0
system serial number : AY00000000
cycle frequency [Hz] : 250000000
timer frequency [Hz] : 250.00
page size [bytes] : 8192
phys. address bits : 44
max. addr. space # : 255
BogoMIPS : 2500.00
platform string : AlphaServer QEMU user-mode VM
cpus detected : 8
cpus active : 4
cpu active mask : 0000000000000095
L1 Icache : n/a
L1 Dcache : n/a
L2 cache : n/a
L3 cache : n/a
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230803214450.647040-4-deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add emulation for /proc/cpuinfo for arm architecture.
The output below mimics output as seen on debian porterboxes.
aarch64 output example:
processor : 0
model name : ARMv8 Processor rev 0 (v8l)
BogoMIPS : 100.00
Features : swp half thumb fast_mult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae aes pmull sha1 sha2 crc32
CPU implementer : 0x41
CPU architecture: 8
CPU variant : 0x1
CPU part : 0xd07
CPU revision : 0
arm 32-bit output example:
processor : 0
model name : ARMv7 Processor rev 5 (armv7l)
BogoMIPS : 100.00
Features : swp half thumb fast_mult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0f
CPU part : 0xc07
CPU revision : 5
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230803214450.647040-3-deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Move the various open_cpuinfo functions into new files.
Move the m68k open_hardware function as well.
All other guest architectures get a boilerplate empty file.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The vxe2 hwcap is not set for programs running in linux-user, but is
set by a Linux kernel running in softmmu. Add it to the former.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230804233748.218935-2-iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
In qemu we catch accesses to files like /proc/cpuinfo or /proc/net/route
and return to the guest contents which would be visible on a real system
(instead what the host would show).
This patch fixes a bug, where for example the accesses
cat /proc////cpuinfo
or
cd /proc && cat cpuinfo
will not be recognized by qemu and where qemu will wrongly show
the contents of the host's /proc/cpuinfo file.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230803214450.647040-2-deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Rather than using a zero tuple to end the table, use a macro
to apply ARRAY_SIZE and pass that on to the convert functions.
This fixes two bugs in which the conversion functions required
that both the target and host masks be non-zero in order to
continue, rather than require both target and host masks be
zero in order to terminate.
This affected mmap_flags_tbl when the host does not support
all of the flags we wish to convert (e.g. MAP_UNINITIALIZED).
Mapping these flags to zero is good enough, and matches how
the kernel ignores bits that are unknown.
Fixes: 4b840f96 ("linux-user: Populate more bits in mmap_flags_tbl")
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
New function that rejects unsupported map types and flags.
In 4b840f96 we should not have accepted MAP_SHARED_VALIDATE
without actually validating the rest of the flags.
Fixes: 4b840f96 ("linux-user: Populate more bits in mmap_flags_tbl")
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
linux-user: Do not adjust image mapping for host page size
linux-user: Adjust initial brk when interpreter is close to executable
util/selfmap: Rewrite using qemu/interval-tree.h
linux-user: Rewrite probe_guest_base
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Merge tag 'pull-lu-20230808' of https://gitlab.com/rth7680/qemu into staging
linux-user: Adjust guest image layout vs reserved_va
linux-user: Do not adjust image mapping for host page size
linux-user: Adjust initial brk when interpreter is close to executable
util/selfmap: Rewrite using qemu/interval-tree.h
linux-user: Rewrite probe_guest_base
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# gpg: Signature made Tue 08 Aug 2023 02:07:42 PM PDT
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [ultimate]
* tag 'pull-lu-20230808' of https://gitlab.com/rth7680/qemu:
linux-user: Rewrite non-fixed probe_guest_base
linux-user: Rewrite fixed probe_guest_base
linux-user: Consolidate guest bounds check in probe_guest_base
linux-user: Remove duplicate CPU_LOG_PAGE from probe_guest_base
util/selfmap: Rewrite using qemu/interval-tree.h
linux-user: Use zero_bss for PT_LOAD with no file contents too
linux-user: Do not adjust zero_bss for host page size
linux-user: Do not adjust image mapping for host page size
linux-user: Adjust initial brk when interpreter is close to executable
linux-user: Use elf_et_dyn_base for ET_DYN with interpreter
linux-user: Use MAP_FIXED_NOREPLACE for initial image mmap
linux-user: Define ELF_ET_DYN_BASE in $guest/target_mman.h
linux-user: Define TASK_UNMAPPED_BASE in $guest/target_mman.h
linux-user: Adjust task_unmapped_base for reserved_va
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use pgb_addr_set to probe for all of the guest addresses,
not just the main executable. Handle the identity map
specially and separately from the search.
If /proc/self/maps is available, utilize the full power
of the interval tree search, rather than a linear search
through the address list.
If /proc/self/maps is not available, increase the skip
between probes so that we do not probe every single page
of the host address space. Choose 1 MiB for 32-bit hosts
(max 4k probes) and 1 GiB for 64-bit hosts (possibly a
large number of probes, but the large step makes it more
likely to find empty space quicker).
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Create a set of subroutines to collect a set of guest addresses,
all of which must be mappable on the host. Use this within the
renamed pgb_fixed subroutine to validate the user's choice of
guest_base specified by the -B command-line option.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The three sets of checks are identical, logically.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The proper logging for probe_guest_base is in the main function.
There is no need to duplicate that in the subroutines.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
We will want to be able to search the set of mappings.
For this patch, the two users iterate the tree in order.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
If p_filesz == 0, then vaddr_ef == vaddr. We can reuse the
code in zero_bss rather than incompletely duplicating it in
load_elf_image.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Remove TARGET_ELF_EXEC_PAGESIZE, and 3 other TARGET_ELF_PAGE* macros
based off of that. Rely on target_mmap to handle guest vs host page
size mismatch.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
While we attempt to load a ET_DYN executable far away from
TASK_UNMAPPED_BASE, we are not completely in control of the
address space layout. If the interpreter lands close to
the executable, leaving insufficient heap space, move brk.
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Helge Deller <deller@gmx.de>
[rth: Re-order after ELF_ET_DYN_BASE patch so that we do not
"temporarily break" tsan, and also to minimize the changes required.
Remove image_info.reserve_brk as unused.]
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Follow the lead of the linux kernel in fs/binfmt_elf.c,
in which an ET_DYN executable which uses an interpreter
(usually a PIE executable) is loaded away from where the
interpreter itself will be loaded.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Use this as extra protection for the guest mapping over
any qemu host mappings.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Copy each guest kernel's default value, then bound it
against reserved_va or the host address space.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Provide default values that are as close as possible to the
values used by the guest's kernel.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Ensure that the chosen values for mmap_next_start and
task_unmapped_base are within the guest address space.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Alpha and 31-bit s390 lack the assembly fragment to handle signals
occurring at the same time as system calls, so they cannot run
linux-user emulation anymore. Drop the host-signal.h files for
them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Message-ID: <20230808120303.585509-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
x32 uses the same signal handling fragments as x86_64, since host_arch
is set to x86_64 when Meson runs. Remove the unnecessary forwarder and
set the host_arch variable properly in configure.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Tested-by: Ilya Leoshkevich <iii@linux.ibm.com>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Message-ID: <20230808120303.585509-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The heap starts at "brk" not "start_brk". With this fixed,
image_info.start_brk is unused and may be removed.
Tested-by: Helge Deller <deller@gmx.de>
Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
do_brk() minimizes calls into target_mmap() by aligning the address
with host page size, which is potentially larger than the target page
size. However, the current implementation of this optimization has two
bugs:
- The start of brk is rounded up with the host page size while brk
advertises an address aligned with the target page size as the
beginning of brk. This makes the beginning of brk unmapped.
- Content clearing after mapping is flawed. The size to clear is
specified as HOST_PAGE_ALIGN(brk_page) - brk_page, but brk_page is
aligned with the host page size so it is always zero.
This optimization actually has no practical benefit. It makes difference
when brk() is called multiple times with values in a range of the host
page size. However, sophisticated memory allocators try to avoid to
make such frequent brk() calls. For example, glibc 2.37 calls brk() to
shrink the heap only when there is a room more than 128 KiB. It is
rare to have a page size larger than 128 KiB if it happens.
Let's remove the optimization to fix the bugs and make the code simpler.
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1616
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-7-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Linux 6.4.7 does nothing when a value smaller than the initial brk is
specified.
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-6-akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
MAP_FIXED_NOREPLACE can ensure the mapped address is fixed without
concerning that the new mapping overwrites something else.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-5-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Later the returned value is compared with -1, and negated errno is not
expected.
Fixes: 00faf08c95 ("linux-user: Don't use MAP_FIXED in do_brk()")
Reviewed-by: Helge Deller <deller@gmx.de>
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-4-akihiko.odaki@daynix.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The man page states:
> Note that older kernels which do not recognize the MAP_FIXED_NOREPLACE
> flag will typically (upon detecting a collision with a preexisting
> mapping) fall back to a “non-MAP_FIXED” type of behavior: they will
> return an address that is different from the requested address.
> Therefore, backward-compatible software should check the returned
> address against the requested address.
https://man7.org/linux/man-pages/man2/mmap.2.html
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-3-akihiko.odaki@daynix.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Passing MAP_FIXED_NOREPLACE to host will fail for reserved_va because
the address space is reserved with mmap. Replace it with MAP_FIXED
in that case.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-Id: <20230802071754.14876-2-akihiko.odaki@daynix.com>
[rth: Expand inline commentary.]
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Set V bit for hwcap if misa is set.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1793
Signed-off-by: Nathan Egge <negge@xiph.org>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Tested-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-Id: <20230803131424.40744-1-negge@xiph.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit 7f4f0d9ea8 ("linux-user/arm: Implement __kernel_cmpxchg with host
atomics") switched to use qatomic_cmpxchg() to swap a word with the memory
content, but missed to endianess-swap the oldval and newval values when
emulating an armeb CPU, which expects words to be stored in big endian in
the guest memory.
The bug can be verified with qemu >= v7.0 on any little-endian host, when
starting the armeb binary of the upx program, which just hangs without
this patch.
Cc: qemu-stable@nongnu.org
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Reported-by: John Reiser <jreiser@BitWagon.com>
Closes: https://github.com/upx/upx/issues/687
Message-Id: <ZMQVnqY+F+5sTNFd@p100>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This reverts commit 518f32221a.
It is causing similar segfaults at least on aarch64, ppc64el
and s390x. Let's revert this one for now and analyze what's
going on later.
Reopens: https://bugs.debian.org/1040981
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Commit 86f04735ac ("linux-user: Fix brk() to release pages") introduced
the possibility for userspace applications to reduce memory footprint by
calling brk() with a lower address and as such free up memory, the same
way as the Linux kernel allows on physical machines.
This change introduced some failures for applications with errors like
- accesing bytes above the brk heap address on the same page,
- freeing memory below the initial brk address,
and introduced a behaviour which isn't done by the kernel (e.g. zeroing
memory above brk).
This patch series fixes those issues and has been tested with existing
programs (e.g. upx).
Additionally one patch fixes running static armhf executables (e.g. fstype)
which was broken since qemu-8.0.
Changes in v2:
- dropped patch to revert d28b3c90cf ("linux-user: Make sure initial brk(0)
is page-aligned")
- rephrased some commit messages
- fixed Cc email addresses, added new ones
- added R-b tags
Helge
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Merge tag 'linux-user-brk-fixes-pull-request' of https://github.com/hdeller/qemu-hppa into staging
linux-user: brk() syscall fixes and armhf static binary fix
Commit 86f04735ac ("linux-user: Fix brk() to release pages") introduced
the possibility for userspace applications to reduce memory footprint by
calling brk() with a lower address and as such free up memory, the same
way as the Linux kernel allows on physical machines.
This change introduced some failures for applications with errors like
- accesing bytes above the brk heap address on the same page,
- freeing memory below the initial brk address,
and introduced a behaviour which isn't done by the kernel (e.g. zeroing
memory above brk).
This patch series fixes those issues and has been tested with existing
programs (e.g. upx).
Additionally one patch fixes running static armhf executables (e.g. fstype)
which was broken since qemu-8.0.
Changes in v2:
- dropped patch to revert d28b3c90cf ("linux-user: Make sure initial brk(0)
is page-aligned")
- rephrased some commit messages
- fixed Cc email addresses, added new ones
- added R-b tags
Helge
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# gpg: Signature made Wed 19 Jul 2023 16:52:19 BST
# gpg: using EDDSA key BCE9123E1AD29F07C049BBDEF712B510A23A0F5F
# gpg: Good signature from "Helge Deller <deller@gmx.de>" [unknown]
# gpg: aka "Helge Deller <deller@kernel.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-brk-fixes-pull-request' of https://github.com/hdeller/qemu-hppa:
linux-user: Fix qemu-arm to run static armhf binaries
linux-user: Fix strace output for old_mmap
linux-user: Fix signed math overflow in brk() syscall
linux-user: Prohibit brk() to to shrink below initial heap address
linux-user: Fix qemu brk() to not zero bytes on current page
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
qemu-user crashes immediately when running static binaries on the armhf
architecture. The problem is the memory layout where the executable is
loaded before the interpreter library, in which case the reserved brk
region clashes with the interpreter code and is released before qemu
tries to start the program.
At load time qemu calculates a brk value for interpreter and executable
each. The fix is to choose the higher one of both.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Andreas Schwab <schwab@suse.de>
Cc: qemu-stable@nongnu.org
Reported-by: Venkata.Pyla@toshiba-tsip.com
Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1040981
The old_mmap syscall (e.g. on i386) hands over the parameters in
a struct. Adjust the strace output to print the correct values.
Signed-off-by: Helge Deller <deller@gmx.de>
Reported-by: John Reiser <jreiser@BitWagon.com>
Closes: https://gitlab.com/qemu-project/qemu/-/issues/1760
Fix the math overflow when calculating the new_malloc_size.
new_host_brk_page and brk_page are unsigned integers. If userspace
reduces the heap, new_host_brk_page is lower than brk_page which results
in a huge positive number (but should actually be negative).
Fix it by adding a proper check and as such make the code more readable.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
Since commit 86f04735ac ("linux-user: Fix brk() to release pages") it's
possible for userspace applications to reduce their memory footprint by
calling brk() with a lower address and free up memory. Before that commit
guest heap memory was never unmapped.
But the Linux kernel prohibits to reduce brk() below the initial memory
address which is set at startup by the set_brk() function in binfmt_elf.c.
Such a range check was missed in commit 86f04735ac.
This patch adds the missing check by storing the initial brk value in
initial_target_brk and verify any new brk addresses against that value.
Tested with the i386 upx binary from
https://github.com/upx/upx/releases/download/v4.0.2/upx-4.0.2-i386_linux.tar.xz
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
The qemu brk() implementation is too aggressive and cleans remaining bytes
on the current page above the last brk address.
But some existing applications are buggy and read/write bytes above their
current heap address. On a phyiscal machine this does not trigger a
runtime error as long as the access happens on the same page. Additionally
the Linux kernel allocates only full pages and does no zeroing on already
allocated pages, even if the brk address is lowered.
Fix qemu to behave the same way as the kernel does. Do not touch already
allocated pages, and - when running with different page sizes of guest and
host - zero out only those memory areas where the host page size is bigger
than the guest page size.
Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: "Markus F.X.J. Oberhumer" <markus@oberhumer.com>
Fixes: 86f04735ac ("linux-user: Fix brk() to release pages")
Cc: qemu-stable@nongnu.org
Buglink: https://github.com/upx/upx/issues/683
elf_hwcap_str() takes a bit number, but compares it for equality with
the HWCAP_S390_* masks. This causes /proc/cpuinfo to display incorrect
hwcaps.
Fix by introducing the HWCAP_S390_NR_* constants and using them in
elf_hwcap_str() instead of the HWCAP_S390_*. While at it, add the
missing nnpa, pcimio and sie hwcaps from the latest kernel.
Output before:
features : esan3 zarch stfle msa
Output after:
features : esan3 zarch stfle msa ldisp eimm etf3eh highgprs vx vxe
Fixes: e19807bee3 ("linux-user/elfload: Introduce elf_hwcap_str() on s390x")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20230627151356.273259-1-iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
In the code for TARGET_NR_clock_adjtime, we set the pointer phtx to
the address of the local variable htx. This means it can never be
NULL, but later in the code we check it for NULL anyway. Coverity
complains about this (CID 1507683) because the NULL check comes after
a call to clock_adjtime() that assumes it is non-NULL.
Since phtx is always &htx, and is used only in three places, it's not
really necessary. Remove it, bringing the code structure in to line
with that for TARGET_NR_clock_adjtime64, which already uses a simple
'&htx' when it wants a pointer to 'htx'.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230623144410.1837261-1-peter.maydell@linaro.org
Since commit fbd3c4cff6 ("linux-user/arm: Mark the commpage
executable") executing bare-metal (linked with rdimon.specs)
cortex-M code fails as:
$ qemu-arm -cpu cortex-m3 ~/hello.exe.m3
qemu-arm: ../../accel/tcg/user-exec.c:492: page_set_flags: Assertion `last <= GUEST_ADDR_MAX' failed.
Aborted (core dumped)
Commit 4f5c67f8df ("linux-user/arm: Take more care allocating
commpage") already took care of not allocating a commpage for
M-profile CPUs, however it had to be reverted as commit 6cda41daa2.
Re-introduce the M-profile fix from commit 4f5c67f8df.
Fixes: fbd3c4cff6 ("linux-user/arm: Mark the commpage executable")
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1755
Reported-by: Christophe Lyon <christophe.lyon@linaro.org>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230711153408.68389-1-philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
These are types not used anymore anywhere else.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: <20230511085056.13809-1-quintela@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The trivial length 0 check can be moved up, simplifying some
of the other cases. The end < start test is handled by
guest_range_valid_untagged.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-27-richard.henderson@linaro.org>
Use page_check_range instead, which uses the interval tree
instead of checking each page individually.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-26-richard.henderson@linaro.org>
