Previously, guest_loaddr was not taken into account when returning an
address from pgb_find_hole when /proc/self/maps was unavailable which
caused an improper guest_base address to be calculated.
This could cause a SIGSEGV later in load_elf_image -> target_mmap for
ET_EXEC type images since the mmap MAP_FIXED flag is specified which
could clobber existing mappings at the address returnd by g2h().
mmap(0xd87000, 16846912, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE|0x100000, -1, 0) = 0xd87000
munmap(0xd87000, 16846912) = 0
write(2, "Locating guest address space @ 0"..., 40Locating guest address space @ 0xd87000) = 40
mmap(0x1187000, 16850944, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS|MAP_NORESERVE, -1, 0) = 0x1187000
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_ACCERR, si_addr=0x2188310} ---
+++ killed by SIGSEGV +++
Now, pgd_find_hole accounts for guest_loaddr in this scenario.
Fixes: ad592e37df ("linux-user: provide fallback pgd_find_hole for bare chroots")
Signed-off-by: Vincent Fazio <vfazio@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210131061948.15990-1-vfazio@xes-inc.com>
[lv: updated it to check if ret == -1]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Previously, pgd_find_hole_fallback assumed that if the build host's libc
had MAP_FIXED_NOREPLACE defined that the address returned by mmap would
match the requested address. This is not a safe assumption for Linux
kernels prior to 4.17
Now, we always compare mmap's resultant address with the requested
address and no longer short-circuit based on MAP_FIXED_NOREPLACE.
Fixes: 2667e069e7 ("linux-user: don't use MAP_FIXED in pgd_find_hole_fallback")
Signed-off-by: Vincent Fazio <vfazio@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210131061930.14554-1-vfazio@xes-inc.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Previously, if the build host's libc did not define MAP_FIXED_NOREPLACE
or if the running kernel didn't support that flag, it was possible for
pgd_find_hole_fallback to munmap an incorrect address which could lead to
SIGSEGV if the range happened to overlap with the mapped address of the
QEMU binary.
mmap(0x1000, 22261224, PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, -1, 0) = 0x7f889d331000
munmap(0x1000, 22261224) = 0
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x84b817} ---
++ killed by SIGSEGV +++
Now, always munmap the address returned by mmap.
Fixes: 2667e069e7 ("linux-user: don't use MAP_FIXED in pgd_find_hole_fallback")
Signed-off-by: Vincent Fazio <vfazio@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210131061849.12615-1-vfazio@xes-inc.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
TILE-Gx was only implemented in linux-user mode, but support for this CPU
was removed from the upstream Linux kernel in 2018, and it has also been
dropped from glibc, so there is no new Linux development taking place with
this architecture. For running the old binaries, users can simply use older
versions of QEMU.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210224183952.80463-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Implementation of Linux user emulation for Hexagon
Some common files modified in addition to new files in linux-user/hexagon
Acked-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <1612763186-18161-31-git-send-email-tsimpson@quicinc.com>
[rth: Fix termbits.h on review by Laurent]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Provide both tagged and untagged versions of access_ok.
In a few places use thread_cpu, as the user is several
callees removed from do_syscall1.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210212184902.1251044-17-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Use g2h_untagged in contexts that have no cpu, e.g. the binary
loaders that operate before the primary cpu is created. As a
colollary, target_mmap and friends must use untagged addresses,
since they are used by the loaders.
Use g2h_untagged on values returned from target_mmap, as the
kernel never applies a tag itself.
Use g2h_untagged on all pc values. The only current user of
tags, aarch64, removes tags from code addresses upon branch,
so "pc" is always untagged.
Use g2h with the cpu context on hand wherever possible.
Use g2h_untagged in lock_user, which will be updated soon.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20210212184902.1251044-13-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is more descriptive than 'unsigned long'.
No functional change, since these match on all linux+bsd hosts.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20210212184902.1251044-4-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Some ELF binaries encode the .bss section as an extension of the data
ones by setting the segment p_memsz > p_filesz. Some other binaries take
a different route and encode it as a stand-alone PT_LOAD segment with
p_filesz = 0 and p_memsz > 0.
Both the encodings are actually correct per ELF specification but the
ELF loader had some troubles in handling the former: with the old logic
it was very likely to get Qemu to crash in zero_bss when trying to
access unmapped memory.
zero_bss isn't meant to allocate whole zero-filled segments but to
"complete" a previously mapped segment with the needed zero bits.
The fix is pretty simple, if the segment is completely zero-filled we
simply allocate one or more pages (according to p_memsz) and avoid
calling zero_bss altogether.
Signed-off-by: Giuseppe Musacchio <thatlemon@gmail.com>
Message-Id: <c9106487-dc4d-120a-bd48-665b3c617287@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Userland ELF binaries using Loongson SIMD instructions have the
HWCAP_LOONGSON_MMI bit set [1].
Binaries compiled for Loongson 3A [2] have the HWCAP_LOONGSON_EXT
bit set for the LQ / SQ instructions.
[1] commit 8e2d5831e4 ("target/mips: Legalize Loongson insn flags")
[2] commit af868995e1 ("target/mips: Add Loongson-3 CPU definition")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-7-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_EQU() macro which
checks if a CPU register has bits set to a specific value.
Use the macro to check the 'Architecture Revision' level
of the Config0 register, which is '2' when the Release 6
ISA is implemented.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-5-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ISA features are usually denoted in read-only bits from
CPU registers. Add the GET_FEATURE_REG_SET() macro which
checks if a CPU register has bits set.
Use the macro to check for MSA (which sets the MSAP bit of
the Config3 register when the ASE implementation is present).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-4-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
We want to add macros similar to GET_FEATURE().
As this one use the 'insn_flags' field, rename it
GET_FEATURE_INSN().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-3-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
As we are going to add more macros, keep the function body clear.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201214003215.344522-2-f4bug@amsat.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Coverity points out that we don't check the return value from
copy_from_user() in vma_dump_size(). This is to some extent
a "can't happen" error since we've already checked the page
with an access_ok() call earlier, but it's simple enough to
handle the error anyway.
Fixes: Coverity CID 1432362
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20201103141532.19912-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
In pgd_find_hole_fallback(), Coverity doesn't like the use
of "if (MAP_FIXED_NOREPLACE || ...)" because it's using a
logical operator on a constant other than 0 or 1 and its
heuristic thinks we might have intended a bitwise operator
instead.
The logic is correct (we are checking whether the host really
has a MAP_FIXED_NOREPLACE or whether we fell back to the
"#define as 0 to ignore" from osdep.h); make Coverity
happier by explicitly writing out the comparison with zero.
Fixes: Coverity CID 1431059
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201103142636.21125-1-peter.maydell@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Use the new generic support for NT_GNU_PROPERTY_TYPE_0.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-12-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is generic support, with the code disabled for all targets.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-11-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is slightly clearer than just using strerror, though
the different forms produced by error_setg_file_open and
error_setg_errno isn't entirely convenient.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-10-richard.henderson@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is a bit clearer than open-coding some of this
with a bare c string.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-9-richard.henderson@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For BTI, we need to know if the executable is static or dynamic,
which means looking for PT_INTERP earlier.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-8-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The second loop uses a loop induction variable, and the first
does not. Transform the first to match the second, to simplify
a following patch moving code between them.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-7-richard.henderson@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fixing this now will clarify following patches.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-6-richard.henderson@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fix an unlikely memory leak in load_elf_image().
Fixes: bf858897b7 ("linux-user: Re-use load_elf_image for the main binary.")
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201021173749.111103-5-richard.henderson@linaro.org
Message-Id: <20201003174944.1972444-1-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
On older kernels which don't implement MAP_FIXED_NOREPLACE the kernel
may still fail to give us the address we asked for despite having
already probed the map for a valid hole. Asserting isn't particularly
useful to the user so let us move the check up and expand the
error_report a little to give them a fighting chance of working around
the problem.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Cc: Bug 1895080 <1895080@bugs.launchpad.net>
Ameliorates: ee94743034
Message-Id: <20200915134317.11110-2-alex.bennee@linaro.org>
info->brk was erroneously set to the end of highest addressed
writable segment which could result it in overlapping the executable.
As per load_elf_binary in fs/binfmt_elf.c in Linux, it should be
set to end of highest addressed segment.
Signed-off-by: Timothy E Baldwin <T.E.Baldwin99@members.leeds.ac.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200728224615.326675-1-T.E.Baldwin99@members.leeds.ac.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Having the MSR[C] bit separate will improve arithmetic that operates
on the carry bit. Having mb_cpu_read_msr() populate MSR[CC] will
prevent the carry copy not matching the carry bit.
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Finish eliminating the sregs array in favor of individual members.
Does not correct the width of EDR, yet.
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
MIPS provides 2 ILP32 ABIs, and therefore 4 possible qemu-mips binaries
with 2 pairs using the same endianess and bitness.
This could lead to an O32 image loading in the N32 binary or vice versa
and in cryptic errors (if lucky that the CPU doesn't match the FPU used)
like :
qemu: Unexpected FPU mode (o32 ELF loaded to qemu-mipsn32[el])
ELF binary's NaN mode not supported by CPU (n32 -> qemu-mips[el])
Add an ABI check macro that could be used while checking the ELF header
that relies in the ABI2 flag to identify n32 binaries and abort instead
early with a more descriptive error :
Invalid ELF image for this architecture
Signed-off-by: Carlo Marcelo Arenas Belón <carenas@gmail.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200823101703.18451-1-carenas@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Plain MAP_FIXED has the undesirable behaviour of splatting exiting
maps so we don't actually achieve what we want when looking for gaps.
We should be using MAP_FIXED_NOREPLACE. As this isn't always available
we need to potentially check the returned address to see if the kernel
gave us what we asked for.
Fixes: ad592e37df ("linux-user: provide fallback pgd_find_hole for bare chroots")
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200724064509.331-9-alex.bennee@linaro.org>
Given we assert the requested address matches what we asked we should
also make that clear in the mmap flags. Otherwise we see failures in
the GitLab environment for some currently unknown but allowable
reason. We use MAP_FIXED_NOREPLACE if we can so we don't just clobber
an existing mapping. Also include the strerror string for a bit more
info on failure.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200701135652.1366-34-alex.bennee@linaro.org>
We rely on the pointer to wrap when accessing the high address of the
COMMPAGE so it lands somewhere reasonable. However on 32 bit hosts we
cannot afford just to map the entire 4gb address range. The old mmap
trial and error code handled this by just checking we could map both
the guest_base and the computed COMMPAGE address.
We can't just manipulate loadaddr to get what we want so we introduce
an offset which pgb_find_hole can apply when looking for a gap for
guest_base that ensures there is space left to map the COMMPAGE
afterwards.
This is arguably a little inefficient for the one 32 bit
value (kuser_helper_version) we need to keep there given all the
actual code entries are picked up during the translation phase.
Fixes: ee94743034
Bug: https://bugs.launchpad.net/qemu/+bug/1880225
Cc: Bug 1880225 <1880225@bugs.launchpad.net>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200605154929.26910-13-alex.bennee@linaro.org>
When running QEMU out of a chroot environment we may not have access
to /proc/self/maps. As there is no other "official" way to introspect
our memory map we need to fall back to the original technique of
repeatedly trying to mmap an address range until we find one that
works.
Fortunately it's not quite as ugly as the original code given we
already re-factored the complications of dealing with the
ARM_COMMPAGE. We do make an attempt to skip over brk() which is about
the only concrete piece of information we have about the address map
at this moment.
Fixes: ee9474303
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200605154929.26910-12-alex.bennee@linaro.org>
Newer clangs rightly spot that you can never exceed the full address
space of 64 bit hosts with:
linux-user/elfload.c:2076:41: error: result of comparison 'unsigned
long' > 18446744073709551615 is always false
[-Werror,-Wtautological-type-limit-compare]
4685 if ((guest_hiaddr - guest_base) > ~(uintptr_t)0) {
4686 ~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~
4687 1 error generated.
So lets limit the check to 32 bit hosts only.
Fixes: ee94743034
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200525131823.715-8-thuth@redhat.com>
[thuth: Use HOST_LONG_BITS < TARGET_ABI_BITS instead of HOST_LONG_BITS == 32]
Signed-off-by: Thomas Huth <thuth@redhat.com>
First we ensure all guest space initialisation logic comes through
probe_guest_base once we understand the nature of the binary we are
loading. The convoluted init_guest_space routine is removed and
replaced with a number of pgb_* helpers which are called depending on
what requirements we have when loading the binary.
We first try to do what is requested by the host. Failing that we try
and satisfy the guest requested base address. If all those options
fail we fall back to finding a space in the memory map using our
recently written read_self_maps() helper.
There are some additional complications we try and take into account
when looking for holes in the address space. We try not to go directly
after the system brk() space so there is space for a little growth. We
also don't want to have to use negative offsets which would result in
slightly less efficient code on x86 when it's unable to use the
segment offset register.
Less mind-binding gotos and hopefully clearer logic throughout.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200513175134.19619-5-alex.bennee@linaro.org>
Searching for memory space can cause problems so lets extend the
CPU_LOG_PAGE output so you can watch init_guest_space fail to
allocate memory. A more involved fix is actually required to make this
function play nicely with the large guard pages the sanitiser likes to
use.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20200403191150.863-5-alex.bennee@linaro.org>
The v8.4-RCPC extension implements some new instructions:
* LDAPUR, LDAPURB, LDAPURH, LDAPRSB, LDAPRSH, LDAPRSW
* STLUR, STLURB, STLURH
These are all in a new subgroup of encodings that sits below the
top-level "Loads and Stores" group in the Arm ARM.
The STLUR* instructions have standard store-release semantics; the
LDAPUR* have Load-AcquirePC semantics, but (as with LDAPR*) we choose
to implement them as the slightly stronger Load-Acquire.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200224172846.13053-4-peter.maydell@linaro.org
The v8.3-RCPC extension implements three new load instructions
which provide slightly weaker consistency guarantees than the
existing load-acquire operations. For QEMU we choose to simply
implement them with a full LDAQ barrier.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20200224172846.13053-3-peter.maydell@linaro.org
Use isar feature tests instead of feature bit tests.
Although none of QEMUs current cpus have VFPv3 without D32,
replace the large comment explaining why with one line that
sets ARM_HWCAP_ARM_VFPv3D16 under the correct conditions.
Mirror the test sequence used in the linux kernel.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200224222232.13807-14-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Enforce a convention that an isar_feature function that tests a
32-bit ID register always has _aa32_ in its name, and one that
tests a 64-bit ID register always has _aa64_ in its name.
We already follow this except for three cases: thumb_div,
arm_div and jazelle, which all need _aa32_ adding.
(As noted in the comment, isar_feature_aa32_fp16_arith()
is an exception in that it currently tests ID_AA64PFR0_EL1,
but will switch to MVFR1 once we've properly implemented
FP16 for AArch32.)
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-2-peter.maydell@linaro.org
With bad luck, we can wind up with no space at all for brk,
which will generally cause the guest malloc to fail.
This bad luck is easier to come by with ET_DYN (PIE) binaries,
where either the stack or the interpreter (ld.so) gets placed
immediately after the main executable.
But there's nothing preventing this same thing from happening
with ET_EXEC (normal) binaries, during probe_guest_base().
In both cases, reserve some extra space via mmap and release
it back to the system after loading the interpreter and
allocating the stack.
The choice of 16MB is somewhat arbitrary. It's enough for libc
to get going, but without being so large that 32-bit guests or
32-bit hosts are in danger of running out of virtual address space.
It is expected that libc will be able to fall back to mmap arenas
after the limited brk space is exhausted.
Launchpad: https://bugs.launchpad.net/qemu/+bug/1749393
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200117230245.5040-1-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
In init_guest_space, we need to mmap guest space. If the return address
of first mmap is not aligned with align, which was set to MAX(SHMLBA,
qemu_host_page_size), we need unmap and a new mmap(space is larger than
first size). The new size is named real_size, which is aligned_size +
qemu_host_page_size. alugned_size is the guest space size. And add a
qemu_host_page_size to avoid memory error when we align real_start
manually (ROUND_UP(real_start, align)). But when SHMLBA >
qemu_host_page_size, the added size will smaller than the size to align,
which can make a mistake(in a mips machine, it appears). So change
real_size from aligned_size +qemu_host_page_size
to aligned_size + align will solve it.
Signed-off-by: Xinyu Li <precinct@mail.ustc.edu.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20191213022919.5934-1-precinct@mail.ustc.edu.cn>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ARMv8.2 introduced support for Data Cache Clean instructions
to PoP (point-of-persistence) - DC CVAP and PoDP (point-of-deep-persistence)
- DV CVADP. Both specify conceptual points in a memory system where all writes
that are to reach them are considered persistent.
The support provided considers both to be actually the same so there is no
distinction between the two. If none is available (there is no backing store
for given memory) both will result in Data Cache Clean up to the point of
coherency. Otherwise sync for the specified range shall be performed.
Signed-off-by: Beata Michalska <beata.michalska@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20191121000843.24844-5-beata.michalska@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This is needed to support debugging PIE ELF binaries running under QEMU
user mode. Currently, `code_offset` and `data_offset` remain unset for
all ELF binaries, so GDB is unable to correctly locate the position of
the binary's text and data.
The fields `code_offset`, and `data_offset` were originally added way
back in 2006 to support debugging of bFMT executables (978efd6aac),
and support was just never added for ELF. Since non-PIE binaries are
loaded at exactly the address specified in the binary, GDB does not need
to relocate any symbols, so the buggy behavior is not normally observed.
http://sourceware.org/gdb/onlinedocs/gdb/General-Query-Packets.html#index-qOffsets-packet
Buglink: https://bugs.launchpad.net/qemu/+bug/1528239
Signed-off-by: Josh Kunz <jkz@google.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190816233422.16715-1-jkz@google.com>
[lv: added link to documentation]
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Add the HWCAP2_* bits from kernel version v5.3-rc3.
Enable the bits corresponding to ARMv8.5-CondM and ARMv8.5-FRINT.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20190809171156.3476-1-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-20-armbru@redhat.com>
QEMU_PPC_FEATURE2_VEC_CRYPTO enables the use
of VSX instructions in libcrypto that are accelerated
by the TCG vector instructions now.
QEMU_PPC_FEATURE2_DARN allows to use the new builtin
qemu_guest_getrandom() function.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20190609143521.19374-1-laurent@vivier.eu>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
