Commit Graph

430 Commits

Author SHA1 Message Date
Peter Maydell
63c1b7de0a linux-user: Report AArch64 hwcap2 fields above bit 31
The AArch64 ELF hwcap2 field is 64 bits, but our get_elf_hwcap2()
works with uint32_t, so it accidentally fails to report any hwcaps
over bit 31.  Use uint64_t here.

The Arm hwcap2 is only 32 bits (because the ELF format makes these
fields be the size of "long" in the ABI), but since it shares the
prototype declaration for get_elf_hwcap2() it is easier to also
expand it to 64 bits.

The only hwcap fields we implement already that are affected by this
are the HBC and MOPS ones, neither of which were implemented in a
previous release, so this doesn't need backporting to older stable
branches.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20231030174000.3792225-3-peter.maydell@linaro.org
2023-11-02 13:36:45 +00:00
Marielle Novastrider
5cfea2487d linux-user/elfload: Add missing arm64 hwcap values
Specifically DIT, LSE2, and MTE3.

We already expose detection of these via the CPUID interface, but
missed these from ELF hwcaps.

Signed-off-by: Marielle Novastrider <marielle@novastrider.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20231029210058.38986-1-marielle@novastrider.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
[PMM: fixed conflict with feature tests moving to cpu-features.h]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2023-11-02 12:52:06 +00:00
Stefan Hajnoczi
516fffc993 linux-user: Fix guest signal remapping after adjusting SIGABRT
linux-user: Implement VDSOs
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Merge tag 'pull-lu-20231030' of https://gitlab.com/rth7680/qemu into staging

linux-user: Fix guest signal remapping after adjusting SIGABRT
linux-user: Implement VDSOs

* tag 'pull-lu-20231030' of https://gitlab.com/rth7680/qemu: (21 commits)
  build: Add update-linux-vdso makefile rule
  linux-user: Show vdso address in /proc/pid/maps
  linux-user/s390x: Add vdso
  linux-user/s390x: Rename __SIGNAL_FRAMESIZE to STACK_FRAME_OVERHEAD
  linux-user/ppc: Add vdso
  linux-user/loongarch64: Add vdso
  linux-user/riscv: Add vdso
  linux-user/hppa: Add vdso
  linux-user/arm: Add vdso
  linux-user/aarch64: Add vdso
  linux-user/x86_64: Add vdso
  linux-user/i386: Add vdso
  linux-user: Add gen-vdso tool
  linux-user: Load vdso image if available
  linux-user: Replace bprm->fd with bprm->src.fd
  linux-user: Use ImageSource in load_symbols
  linux-user: Use ImageSource in load_elf_image
  linux-user: Do not clobber bprm_buf swapping ehdr
  linux-user: Tidy loader_exec
  linux-user: Introduce imgsrc_read, imgsrc_read_alloc
  ...

Conflicts:
  linux-user/arm/signal.c
  Fix an #include context conflict.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2023-10-31 07:12:40 +09:00
Richard Henderson
5d94c2ffa8 linux-user: Show vdso address in /proc/pid/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>
2023-10-30 13:41:56 -07:00
Richard Henderson
b63c6b97f8 linux-user/s390x: Add vdso
Acked-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:56 -07:00
Richard Henderson
e34136d930 linux-user/ppc: Add vdso
Add support in gen-vdso-elfn.c.inc for the DT_PPC64_OPT
dynamic tag: this is an integer, so does not need relocation.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:56 -07:00
Richard Henderson
00cc2934b2 linux-user/loongarch64: Add vdso
Requires a relatively recent binutils version in order to avoid
spurious R_LARCH_NONE relocations.  The presence of these relocs
are diagnosed by our gen-vdso tool.

Tested-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
468c1bb5ca linux-user/riscv: Add vdso
Acked-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
c7bc2a8fb1 linux-user/hppa: Add vdso
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
a9f495b93f linux-user/arm: Add vdso
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
ee95fae075 linux-user/aarch64: Add vdso
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
6b1a9d38b5 linux-user/x86_64: Add vdso
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
a1367443ba linux-user/i386: Add vdso
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1267
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
c40f621a19 linux-user: Load vdso image if available
The vdso image will be pre-processed into a C data array, with
a simple list of relocations to perform, and identifying the
location of signal trampolines.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
86cf82dc9f linux-user: Use ImageSource in load_symbols
Aside from the section headers, we're unlikely to hit the
ImageSource cache on guest executables.  But the interface
for imgsrc_read_* is better.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
3bd0238638 linux-user: Use ImageSource in load_elf_image
Change parse_elf_properties as well, as the bprm_buf argument
ties the two functions closely.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Richard Henderson
40d487eecf linux-user: Do not clobber bprm_buf swapping ehdr
Rearrange the allocation of storage for ehdr between load_elf_image
and load_elf_binary.  The same set of copies are done, but we don't
modify bprm_buf, which will be important later.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-30 13:41:55 -07:00
Peter Maydell
5a534314a8 target/arm: Move feature test functions to their own header
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
2023-10-27 11:44:32 +01:00
Jiajie Chen
a9f6004f67 linux-user/elfload: Enable LSX/LASX in HWCAP for LoongArch
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>
2023-10-18 15:32:16 -07:00
Richard Henderson
e6e66b0328 linux-user: Fixes for zero_bss
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>
2023-10-18 15:32:16 -07:00
Richard Henderson
b77af26e97 accel/tcg: Replace CPUState.env_ptr with cpu_env()
Reviewed-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-10-04 11:03:54 -07:00
Peter Maydell
706a92fbfa target/arm: Enable FEAT_MOPS for CPU 'max'
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
2023-09-21 16:07:14 +01:00
Peter Maydell
3039b090f2 target/arm: Implement FEAT_HBC
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>
2023-09-21 16:07:13 +01:00
Peter Maydell
429b7e0107 linux-user/elfload.c: Report previously missing arm32 hwcaps
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>
2023-09-21 14:45:57 +01:00
Peter Maydell
23d7f14da4 linux-user/elfload.c: Add missing arm and arm64 hwcap values
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>
2023-09-21 14:45:57 +01:00
Peter Maydell
e2e40a7790 linux-user/elfload.c: Correct SME feature names reported in cpuinfo
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>
2023-09-21 14:45:57 +01:00
Richard Henderson
f6d4554242 linux-user: Remove ELF_START_MMAP and image_info.start_mmap
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>
2023-09-01 13:34:50 -07:00
Richard Henderson
aec338d63b linux-user: Adjust brk for load_bias
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>
2023-09-01 13:34:18 -07:00
Helge Deller
a55b9e7226 linux-user: Emulate /proc/cpuinfo on aarch64 and arm
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>
2023-09-01 13:33:36 -07:00
Ilya Leoshkevich
ffc8453bd2 linux-user/elfload: Enable vxe2 on s390x
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>
2023-08-23 12:06:44 +02:00
Richard Henderson
dd55885516 linux-user: Rewrite non-fixed probe_guest_base
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>
2023-08-08 13:41:55 -07:00
Richard Henderson
06f38c6688 linux-user: Rewrite fixed probe_guest_base
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>
2023-08-08 13:33:22 -07:00
Richard Henderson
0c441aeb39 linux-user: Consolidate guest bounds check in probe_guest_base
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
435c042fdc linux-user: Remove duplicate CPU_LOG_PAGE from probe_guest_base
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
3ce3dd8ca9 util/selfmap: Rewrite using qemu/interval-tree.h
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
5f4e5b3409 linux-user: Use zero_bss for PT_LOAD with no file contents too
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
2d385be615 linux-user: Do not adjust zero_bss for host page size
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>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2023-08-08 13:27:17 -07:00
Richard Henderson
e3d97d5c5d linux-user: Do not adjust image mapping for host page size
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>
2023-08-08 13:27:17 -07:00
Helge Deller
1f356e8c01 linux-user: Adjust initial brk when interpreter is close to executable
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
1ea06ded0d linux-user: Use elf_et_dyn_base for ET_DYN with interpreter
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>
2023-08-08 13:27:17 -07:00
Richard Henderson
ad25051bae linux-user: Use MAP_FIXED_NOREPLACE for initial image mmap
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>
2023-08-08 13:27:17 -07:00
Akihiko Odaki
2aea137a42 linux-user: Do not align brk with host page size
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>
2023-08-06 16:46:03 -07:00
Nathan Egge
4333f0924c linux-user/elfload: Set V in ELF_HWCAP for RISC-V
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>
2023-08-06 10:10:11 -07:00
Michael Tokarev
4ea3fa99be Revert "linux-user: Fix qemu-arm to run static armhf binaries"
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>
2023-07-22 19:54:22 +03:00
Peter Maydell
67d1f0a390 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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 =K3Va
 -----END PGP SIGNATURE-----

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

# -----BEGIN PGP SIGNATURE-----
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# XwkUAQCKb/lkI3IYxiqO48rVyHtLPtkXd+WttFpeZ076p73LTgD+IEpHZL4WV1Rw
# 4+eqW9vswjZwp1xm9bItLdnP2hkyUgI=
# =K3Va
# -----END PGP SIGNATURE-----
# 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>
2023-07-20 09:53:52 +01:00
Helge Deller
518f32221a linux-user: Fix qemu-arm to run static armhf binaries
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
2023-07-18 20:42:05 +02:00
Ilya Leoshkevich
7f114a5807 linux-user/elfload: Fix /proc/cpuinfo features: on s390x
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>
2023-07-18 09:36:27 +02:00
Philippe Mathieu-Daudé
d713cf4d6c linux-user/arm: Do not allocate a commpage at all for M-profile CPUs
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>
2023-07-15 08:02:33 +01:00
Ilya Leoshkevich
78a1e153f9 linux-user: elfload: Add more initial s390x PSW bits
Make the PSW look more similar to the real s390x userspace PSW.
Except for being there, the newly added bits should not affect the
userspace code execution.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20230704081506.276055-2-iii@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2023-07-10 15:34:23 +02:00
Andrew Jeffery
e928907105 linux-user: elfload: Specify -R is an option for qemu-user binaries
Given several different concepts are suggested for investigation, let's
not confuse e.g. ulimit's -R with what was actually intended.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2023-06-10 09:40:46 +03:00