If low-address-protection is active, unaligned stores to non-protected
parts of lowcore lead to protection exceptions. The reason is that in
such cases tlb_fill() call in store_helper_unaligned() covers
[0, addr + size) range, which contains the protected portion of
lowcore. This range is too large.
The most straightforward fix would be to make sure we stay within the
original [addr, addr + size) range. However, if an unaligned access
affects a single page, we don't need to call tlb_fill() in
store_helper_unaligned() at all, since it would be identical to
the previous tlb_fill() call in store_helper(), and therefore a no-op.
If an unaligned access covers multiple pages, this situation does not
occur.
Therefore simply skip TLB handling in store_helper_unaligned() if we
are dealing with a single page.
Fixes: 2bcf018340 ("s390x/tcg: low-address protection support")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-Id: <20220711185640.3558813-2-iii@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Allow retrieving only a subset of statistics. This can be useful
for example in order to plot a subset of the statistics many times
a second: KVM publishes ~40 statistics for each vCPU on x86; retrieving
and serializing all of them would be useless.
Another use will be in HMP in the following patch; implementing the
filter in the backend is easy enough that it was deemed okay to make
this a public interface.
Example:
{ "execute": "query-stats",
"arguments": {
"target": "vcpu",
"vcpus": [ "/machine/unattached/device[2]",
"/machine/unattached/device[4]" ],
"providers": [
{ "provider": "kvm",
"names": [ "l1d_flush", "exits" ] } } }
{ "return": {
"vcpus": [
{ "path": "/machine/unattached/device[2]"
"providers": [
{ "provider": "kvm",
"stats": [ { "name": "l1d_flush", "value": 41213 },
{ "name": "exits", "value": 74291 } ] } ] },
{ "path": "/machine/unattached/device[4]"
"providers": [
{ "provider": "kvm",
"stats": [ { "name": "l1d_flush", "value": 16132 },
{ "name": "exits", "value": 57922 } ] } ] } ] } }
Extracted from a patch by Mark Kanda.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow retrieving the statistics from a specific provider only.
This can be used in the future by HMP commands such as "info
sync-profile" or "info profile". The next patch also adds
filter-by-provider capabilities to the HMP equivalent of
query-stats, "info stats".
Example:
{ "execute": "query-stats",
"arguments": {
"target": "vm",
"providers": [
{ "provider": "kvm" } ] } }
The QAPI is a bit more verbose than just a list of StatsProvider,
so that it can be subsequently extended with filtering of statistics
by name.
If a provider is specified more than once in the filter, each request
will be included separately in the output.
Extracted from a patch by Mark Kanda.
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce a simple filtering of statistics, that allows to retrieve
statistics for a subset of the guest vCPUs. This will be used for
example by the HMP monitor, in order to retrieve the statistics
for the currently selected CPU.
Example:
{ "execute": "query-stats",
"arguments": {
"target": "vcpu",
"vcpus": [ "/machine/unattached/device[2]",
"/machine/unattached/device[4]" ] } }
Extracted from a patch by Mark Kanda.
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add support for querying fd-based KVM stats - as introduced by Linux kernel
commit:
cb082bfab59a ("KVM: stats: Add fd-based API to read binary stats data")
This allows the user to analyze the behavior of the VM without access
to debugfs.
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We have about 30 instances of the typo/variant spelling 'writeable',
and over 500 of the more common 'writable'. Standardize on the
latter.
Change produced with:
sed -i -e 's/\([Ww][Rr][Ii][Tt]\)[Ee]\([Aa][Bb][Ll][Ee]\)/\1\2/g' $(git grep -il writeable)
and then hand-undoing the instance in linux-headers/linux/kvm.h.
Most of these changes are in comments or documentation; the
exceptions are:
* a local variable in accel/hvf/hvf-accel-ops.c
* a local variable in accel/kvm/kvm-all.c
* the PMCR_WRITABLE_MASK macro in target/arm/internals.h
* the EPT_VIOLATION_GPA_WRITABLE macro in target/i386/hvf/vmcs.h
(which is never used anywhere)
* the AR_TYPE_WRITABLE_MASK macro in target/i386/hvf/vmx.h
(which is never used anywhere)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 20220505095015.2714666-1-peter.maydell@linaro.org
This patch decouples checkpoints and async events.
It was a tricky part of replay implementation. Now it becomes
much simpler and easier to maintain.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <165364837856.688121.8785039478408995979.stgit@pasha-ThinkPad-X280>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Header guard symbols should match their file name to make guard
collisions less likely.
Cleaned up with scripts/clean-header-guards.pl, followed by some
renaming of new guard symbols picked by the script to better ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220506134911.2856099-2-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[Change to generated file ebpf/rss.bpf.skeleton.h backed out]
Coverity reports out-of-bound accesses within cputlb.c.
This should be a false positive due to how the index is
decoded from MemOpIdx. To be fair, nothing is checking
the correct bounds during encoding either.
Assert index in range before use, both to catch user errors
and to pacify static analysis.
Fixes: Coverity CID 1487120, 1487127, 1487170, 1487196, 1487215, 1487238
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220401170813.318609-1-richard.henderson@linaro.org>
Inside qemu_log, we perform qemu_log_trylock/unlock, which need
not be done if we have already performed the lock beforehand.
Always check the result of qemu_log_trylock -- only checking
qemu_loglevel_mask races with the acquisition of the lock on
the logfile.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-10-richard.henderson@linaro.org>
This function can fail, which makes it more like ftrylockfile
or pthread_mutex_trylock than flockfile or pthread_mutex_lock,
so rename it.
To closer match the other trylock functions, release rcu_read_lock
along the failure path, so that qemu_log_unlock need not be called
on failure.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220417183019.755276-8-richard.henderson@linaro.org>
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.
This avoids the need for a constructor initialization too.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace a config-time define with a compile time condition
define (compatible with clang and gcc) that must be declared prior to
its usage. This avoids having a global configure time define, but also
prevents from bad usage, if the config header wasn't included before.
This can help to make some code independent from qemu too.
gcc supports __BYTE_ORDER__ from about 4.6 and clang from 3.2.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[ For the s390x parts I'm involved in ]
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220323155743.1585078-7-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
This commit only touches allocations with size arguments of the form
sizeof(T).
Patch created mechanically with:
$ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
--macro-file scripts/cocci-macro-file.h FILES...
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
In some cases, cpu->exit_request can be false after handling the
interrupt, leading to another TB being executed instead of returning
to the main loop.
Fix this by returning true unconditionally when in single-step mode.
Fixes: ba3c35d9c4 ("tcg/cpu-exec: precise single-stepping after an interrupt")
Signed-off-by: Luc Michel <lmichel@kalray.eu>
Message-Id: <20220214132656.11397-1-lmichel@kalray.eu>
[rth: Unlock iothread mutex; simplify indentation]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Fix safe_syscall_base for sparc64.
Fix host signal handling for sparc64-linux.
Speedups for jump cache and work list probing.
Fix for exception replays.
Raise guest SIGBUS for user-only misaligned accesses.
# gpg: Signature made Fri 11 Feb 2022 01:27:16 GMT
# gpg: using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg: issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A 05C0 64DF 38E8 AF7E 215F
* remotes/rth-gitlab/tags/pull-tcg-20220211: (34 commits)
tests/tcg/multiarch: Add sigbus.c
tcg/sparc: Support unaligned access for user-only
tcg/sparc: Add tcg_out_jmpl_const for better tail calls
tcg/sparc: Use the constant pool for 64-bit constants
tcg/sparc: Convert patch_reloc to return bool
tcg/sparc: Improve code gen for shifted 32-bit constants
tcg/sparc: Add scratch argument to tcg_out_movi_int
tcg/sparc: Split out tcg_out_movi_imm32
tcg/sparc: Use tcg_out_movi_imm13 in tcg_out_addsub2_i64
tcg/mips: Support unaligned access for softmmu
tcg/mips: Support unaligned access for user-only
tcg/arm: Support raising sigbus for user-only
tcg/arm: Reserve a register for guest_base
tcg/arm: Support unaligned access for softmmu
tcg/arm: Check alignment for ldrd and strd
tcg/arm: Remove use_armv6_instructions
tcg/arm: Remove use_armv5t_instructions
tcg/arm: Drop support for armv4 and armv5 hosts
tcg/loongarch64: Support raising sigbus for user-only
tcg/tci: Support raising sigbus for user-only
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We can't always guarantee we get to the end of a translator loop.
Although this can happen for a variety of reasons it does happen more
often on x86 system emulation when an instruction spans across to an
un-faulted page. This caused confusion of the instruction tracking
data resulting in apparent reverse execution (at least from the
plugins point of view).
Fix this by moving the reset code to plugin_gen_tb_start so we always
start with a clean slate.
We unconditionally reset tcg_ctx->plugin_insn as the
plugin_insn_append code uses this as a proxy for knowing if plugins
are enabled for the current instruction. Otherwise we can hit a race
where a previously instrumented thread leaves a stale value after the
main thread exits and disables instrumentation.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/824
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220204204335.1689602-27-alex.bennee@linaro.org>
Commit aff0e204cb introduced CF_NOIRQ usage,
but one case was forgotten. Record/replay uses one special TB which is not
really executed, but used to cause a correct exception in replay mode.
This patch adds CF_NOIRQ flag for such block.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <164362834054.1754532.7678416881159817273.stgit@pasha-ThinkPad-X280>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>