Keep system/watchpoint.c accelerator-agnostic by moving
TCG specific code to accel/tcg/watchpoint.c. Update meson.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240111162032.43378-1-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231208113529.74067-7-philmd@linaro.org>
Add an update buffer where all block updates are staged.
Flush or discard updates properly, so we should never see
half-completed block writes in pflash storage.
Drop a bunch of FIXME comments ;)
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240108160900.104835-4-kraxel@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Use the helper functions we have to read/write multi-byte values
in correct byte order.
Suggested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240108160900.104835-3-kraxel@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Move the offset calculation, do it once at the start of the function and
let the 'p' variable point directly to the memory location which should
be updated. This makes it simpler to update other buffers than
pfl->storage in an upcoming patch. No functional change.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240108160900.104835-2-kraxel@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
This is a follow-up on commit 89965db43c "hw/isa/piix3: Avoid Xen-specific
variant of piix3_write_config()" which introduced
piix_intx_routing_notifier_xen(). This function is implemented in board code but
accesses the PCI configuration space of the PIIX ISA function to determine the
PCI interrupt routes. Avoid this by reusing pci_device_route_intx_to_irq() which
makes piix_intx_routing_notifier_xen() more device-agnostic.
One remaining improvement would be making piix_intx_routing_notifier_xen()
agnostic towards the number of PCI interrupt routes and move it to xen-hvm.
This might be useful for possible Q35 Xen efforts but remains a future exercise
for now.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240107231623.5282-1-shentey@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The 16MiB flash device is only used by the deprecated shix machine.
Its code it old and unmaintained, and has never been adapted to the
QOM architecture. It still contains debug statements and uses global
variables. It is time to deprecate it.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240109083053.2581588-3-sam@rfc1149.net>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
The shix machine has been designed and used at Télécom Paris from 2003
to 2010. It had been added to QEMU in 2005 and has not been maintained
since. Since nobody is using the physical board anymore nor interested
in maintaining the QEMU port, it is time to deprecate it.
Signed-off-by: Samuel Tardieu <sam@rfc1149.net>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240109083053.2581588-2-sam@rfc1149.net>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231208113529.74067-6-philmd@linaro.org>
pmu_init() register its event checking the pm_event::supported()
handler. For INST_RETIRED, the event is only registered and the
bit enabled in the PMU Common Event Identification register when
icount is enabled as ICOUNT_PRECISE.
PMU events are TCG-only, hardware accelerators handle them
directly. Unfortunately we register the events in non-TCG builds,
leading to linking error such:
ld: Undefined symbols:
_icount_to_ns, referenced from:
_instructions_ns_per in target_arm_helper.c.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)
As a kludge, give a hint to the compiler by asserting the
pm_event::get_count() and pm_event::ns_per_count() handler will
only be called under this icount mode.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231208113529.74067-5-philmd@linaro.org>
Rather than having to lookup for what the 0, 1, 2, ...
icount values are, use a enum definition.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231208113529.74067-4-philmd@linaro.org>
Following the example documented since commit e3fe3988d7 ("error:
Document Error API usage rules"), have icount_configure()
return a boolean indicating whether an error is set or not.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231208113529.74067-2-philmd@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231207105426.49339-3-philmd@linaro.org>
Except helper_load_pcc(), all helpers from sys_helper.c
are system-emulation specific. In preparation of restricting
sys_helper.c to system emulation, extract helper_load_pcc()
to clk_helper.c.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231207105426.49339-2-philmd@linaro.org>
Since previous commit, tb_invalidate_phys_page() is not used
anymore in system emulation. Make it static for user emulation
and remove its public declaration in "exec/translate-all.h".
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20231130205600.35727-1-philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Commit e3f7c801f1 introduced the TCGCPUOps::debug_check_breakpoint()
handler, and commit 10c37828b2 "moved breakpoint recognition outside
of translation", so "we no longer need to flush any TBs when changing
BPs".
The last target using tb_invalidate_phys_addr() was converted to the
debug_check_breakpoint(), so this function is now unused. Remove it.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231130203241.31099-1-philmd@linaro.org>
When icount and ibreak exceptions are due to happen on the same address
icount has higher precedence.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231130171920.3798954-3-jcmvbkbc@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Don't embed ibreak exception generation into TB and don't invalidate TB
on ibreak address change. Add CPUBreakpoint pointers to xtensa
CPUArchState, use cpu_breakpoint_insert/cpu_breakpoint_remove_by_ref to
manage ibreak breakpoints and provide TCGCPUOps::debug_check_breakpoint
callback that recognizes valid instruction breakpoints.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20231130171920.3798954-2-jcmvbkbc@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
'can_do_io' is specific to TCG. It was added to other
accelerators in 626cf8f4c6 ("icount: set can_do_io outside
TB execution"), then likely copy/pasted in commit c97d6d2cdf
("i386: hvf: add code base from Google's QEMU repository").
Having it set in non-TCG code is confusing, so remove it from
QTest / HVF / KVM.
Fixes: 626cf8f4c6 ("icount: set can_do_io outside TB execution")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231129205037.16849-1-philmd@linaro.org>
'tcg_cflags' is specific to TCG.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231130075958.21285-1-philmd@linaro.org>
Both cryptodev_backend_set_throttle() and CryptoDevBackendClass::init()
can set their Error** argument. Do not ignore them, return early
on failure. Without that, running into another failure trips
error_setv()'s assertion. Use the ERRP_GUARD() macro as suggested
in commit ae7c80a7bd ("error: New macro ERRP_GUARD()").
Cc: qemu-stable@nongnu.org
Fixes: e7a775fd9f ("cryptodev: Account statistics")
Fixes: 2580b452ff ("cryptodev: support QoS")
Reviewed-by: zhenwei pi <pizhenwei@bytedance.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20231120150418.93443-1-philmd@linaro.org>
This conversion is pretty straight-forward. Standardized some formatting
so the +0 and +4 offset cases can recycle the same message.
Signed-off-by: Daniel Hoffman <dhoff749@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231118231129.2840388-1-dhoff749@gmail.com>
[PMD: Fixed few string formats]
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
By default, the timeout to receive any specified event from the QEMU VM is 60
seconds set by the python avocado test framework. Please see event_wait() and
events_wait() in python/qemu/machine/machine.py. If the matching event is not
triggered within that interval, an asyncio.TimeoutError is generated. Since the
timeout for the bits avocado test is 200 secs, we need to make event_wait()
timeout of the same value as well so that an early timeout is not triggered by
the avocado framework.
CC: peter.maydell@linaro.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2077
Signed-off-by: Ani Sinha <anisinha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20240117042556.3360190-1-anisinha@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
j is used while loading an ELF file to byteswap segments'
data. If data is larger than 2GB an overflow may happen.
So j should be elf_word.
This commit fixes a minor bug: it's unlikely anybody is trying to
load ELF files with 2GB+ segments for wrong-endianness targets,
but if they did, it wouldn't work correctly.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Cc: qemu-stable@nongnu.org
Fixes: 7ef295ea5b ("loader: Add data swap option to load-elf")
Signed-off-by: Anastasia Belova <abelova@astralinux.ru>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
It's found that some of the CPU type names in the array of valid
CPU types are invalid because their corresponding classes aren't
registered, as reported by Peter Maydell.
[gshan@gshan build]$ ./qemu-system-arm -machine virt -cpu cortex-a9
qemu-system-arm: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, (null), (null), (null),
(null), (null), (null), (null), (null), (null), (null), (null), max
Fix it by consolidating the array of valid CPU types. After it's
applied, we have the following output when TCG is enabled.
[gshan@gshan build]$ ./qemu-system-arm -machine virt -cpu cortex-a9
qemu-system-arm: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, max
[gshan@gshan build]$ ./qemu-system-aarch64 -machine virt -cpu cortex-a9
qemu-system-aarch64: Invalid CPU model: cortex-a9
The valid models are: cortex-a7, cortex-a15, cortex-a35, cortex-a55,
cortex-a72, cortex-a76, cortex-a710, a64fx, neoverse-n1, neoverse-v1,
neoverse-n2, cortex-a53, cortex-a57, max
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2084
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Message-id: 20240111051054.83304-1-gshan@redhat.com
Fixes: fa8c617791 ("hw/arm/virt: Check CPU type in machine_run_board_init()")
Signed-off-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
There were some regressions introduced with Qemu v8.2 on the hppa/hppa64
target, e.g.:
- 32-bit HP-UX crashes on B160L (32-bit) machine
- NetBSD boot failure due to power button in page zero
- NetBSD FPU detection failure
- OpenBSD 7.4 boot failure
This patch series fixes those known regressions and additionally:
- allows usage of the max. 3840MB of memory (instead of 3GB),
- adds support for the qemu --nodefaults option (to debug other devices)
This patch set will not fix those known (non-regression) bugs:
- HP-UX and NetBSD still fail to boot on the new 64-bit C3700 machine
- Linux kernel will still fail to boot on C3700 as long as kernel modules are used.
Changes v2->v3:
- Added comment about Figures H-10 and H-11 in the parisc2.0 spec
in patch which calculate PDC address translation if PSW.W=0
- Introduce and use hppa_set_ior_and_isr()
- Use drive_get_max_bus(IF_SCSI), nd_table[] and serial_hd() to check
if default devices should be created
- Added Tested-by and Reviewed-by tags
Changes v1->v2:
- fix OpenBSD boot with SeaBIOS v15 instead of v14
- commit message enhancements suggested by BALATON Zoltan
- use uint64_t for ram_max in patch #1
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQS86RI+GtKfB8BJu973ErUQojoPXwUCZaImPQAKCRD3ErUQojoP
X2C5AP9fbIkCni45JU6KC6OmFsCbAReRQCPwLO+MzR8/us2ywgD+PsGxSBk8ASxM
nqtv3J9JC3i+XSnbtwLV+qChnO+IXwc=
=FAMY
-----END PGP SIGNATURE-----
Merge tag 'hppa-fixes-8.2-pull-request' of https://github.com/hdeller/qemu-hppa into staging
target/hppa qemu v8.2 regression fixes
There were some regressions introduced with Qemu v8.2 on the hppa/hppa64
target, e.g.:
- 32-bit HP-UX crashes on B160L (32-bit) machine
- NetBSD boot failure due to power button in page zero
- NetBSD FPU detection failure
- OpenBSD 7.4 boot failure
This patch series fixes those known regressions and additionally:
- allows usage of the max. 3840MB of memory (instead of 3GB),
- adds support for the qemu --nodefaults option (to debug other devices)
This patch set will not fix those known (non-regression) bugs:
- HP-UX and NetBSD still fail to boot on the new 64-bit C3700 machine
- Linux kernel will still fail to boot on C3700 as long as kernel modules are used.
Changes v2->v3:
- Added comment about Figures H-10 and H-11 in the parisc2.0 spec
in patch which calculate PDC address translation if PSW.W=0
- Introduce and use hppa_set_ior_and_isr()
- Use drive_get_max_bus(IF_SCSI), nd_table[] and serial_hd() to check
if default devices should be created
- Added Tested-by and Reviewed-by tags
Changes v1->v2:
- fix OpenBSD boot with SeaBIOS v15 instead of v14
- commit message enhancements suggested by BALATON Zoltan
- use uint64_t for ram_max in patch #1
# -----BEGIN PGP SIGNATURE-----
#
# iHUEABYKAB0WIQS86RI+GtKfB8BJu973ErUQojoPXwUCZaImPQAKCRD3ErUQojoP
# X2C5AP9fbIkCni45JU6KC6OmFsCbAReRQCPwLO+MzR8/us2ywgD+PsGxSBk8ASxM
# nqtv3J9JC3i+XSnbtwLV+qChnO+IXwc=
# =FAMY
# -----END PGP SIGNATURE-----
# gpg: Signature made Sat 13 Jan 2024 05:57:17 GMT
# 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 'hppa-fixes-8.2-pull-request' of https://github.com/hdeller/qemu-hppa:
target/hppa: Update SeaBIOS-hppa to version 15
target/hppa: Fix IOR and ISR on error in probe
target/hppa: Fix IOR and ISR on unaligned access trap
target/hppa: Export function hppa_set_ior_and_isr()
target/hppa: Avoid accessing %gr0 when raising exception
hw/hppa: Move software power button address back into PDC
target/hppa: Fix PDC address translation on PA2.0 with PSW.W=0
hw/pci-host/astro: Add missing astro & elroy registers for NetBSD
hw/hppa/machine: Disable default devices with --nodefaults option
hw/hppa/machine: Allow up to 3840 MB total memory
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
- Het's cleanup on migration qmp command paths
- Fabiano's migration cleanups and test improvements
- Fabiano's patch to re-enable multifd-cancel test
- Peter's migration doc reorganizations
- Nick Briggs's fix for Solaries build on rdma
-----BEGIN PGP SIGNATURE-----
iIgEABYKADAWIQS5GE3CDMRX2s990ak7X8zN86vXBgUCZaX1PhIccGV0ZXJ4QHJl
ZGhhdC5jb20ACgkQO1/MzfOr1wZSzwEAq6sp/ylNHLzNoMdWL28JLqCsb4DPYH2i
u7XgYgT1qDAA/0vwoe4a5uFn1aaGCS+2d2syjJ8kOE7h+eZrbK520jsA
=1zUG
-----END PGP SIGNATURE-----
Merge tag 'migration-20240116-pull-request' of https://gitlab.com/peterx/qemu into staging
Migration pull request 2nd batch for 9.0
- Het's cleanup on migration qmp command paths
- Fabiano's migration cleanups and test improvements
- Fabiano's patch to re-enable multifd-cancel test
- Peter's migration doc reorganizations
- Nick Briggs's fix for Solaries build on rdma
# -----BEGIN PGP SIGNATURE-----
#
# iIgEABYKADAWIQS5GE3CDMRX2s990ak7X8zN86vXBgUCZaX1PhIccGV0ZXJ4QHJl
# ZGhhdC5jb20ACgkQO1/MzfOr1wZSzwEAq6sp/ylNHLzNoMdWL28JLqCsb4DPYH2i
# u7XgYgT1qDAA/0vwoe4a5uFn1aaGCS+2d2syjJ8kOE7h+eZrbK520jsA
# =1zUG
# -----END PGP SIGNATURE-----
# gpg: Signature made Tue 16 Jan 2024 03:17:18 GMT
# gpg: using EDDSA key B9184DC20CC457DACF7DD1A93B5FCCCDF3ABD706
# gpg: issuer "peterx@redhat.com"
# gpg: Good signature from "Peter Xu <xzpeter@gmail.com>" [marginal]
# gpg: aka "Peter Xu <peterx@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: B918 4DC2 0CC4 57DA CF7D D1A9 3B5F CCCD F3AB D706
* tag 'migration-20240116-pull-request' of https://gitlab.com/peterx/qemu:
migration/rdma: define htonll/ntohll only if not predefined
docs/migration: Further move virtio to be feature of migration
docs/migration: Further move vfio to be feature of migration
docs/migration: Organize "Postcopy" page
docs/migration: Split "dirty limit"
docs/migration: Split "Postcopy"
docs/migration: Split "Debugging" and "Firmware"
docs/migration: Split "Backwards compatibility" separately
docs/migration: Convert virtio.txt into rST
docs/migration: Create index page
docs/migration: Create migration/ directory
tests/qtest: Re-enable multifd cancel test
tests/qtest/migration: Use the new migration_test_add
tests/qtest/migration: Add a wrapper to print test names
tests/qtest/migration: Print migration incoming errors
migration: Report error in incoming migration
migration/multifd: Change multifd_pages_init argument
migration/multifd: Remove QEMUFile from where it is not needed
migration/multifd: Remove MultiFDPages_t::packet_num
migration: Simplify initial conditionals in migration for better readability
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When variables are used without being initialized, there is potential
to take advantage of data that was pre-existing on the stack from an
earlier call, to drive an exploit.
It is good practice to always initialize variables, and the compiler
can warn about flaws when -Wuninitialized is present. This warning,
however, is by no means foolproof with its output varying depending
on compiler version and which optimizations are enabled.
The -ftrivial-auto-var-init option can be used to tell the compiler
to always initialize all variables. This increases the security and
predictability of the program, closing off certain attack vectors,
reducing the risk of unsafe memory disclosure.
While the option takes several possible values, using 'zero' is
considered to be the option that is likely to lead to semantically
correct or safe behaviour[1]. eg sizes/indexes are not likely to
lead to out-of-bounds accesses when initialized to zero. Pointers
are less likely to point something useful if initialized to zero.
Even with -ftrivial-auto-var-init=zero set, GCC will still issue
warnings with -Wuninitialized if it discovers a problem, so we are
not loosing diagnostics for developers, just hardening runtime
behaviour and making QEMU behave more predictably in case of hitting
bad codepaths.
[1] https://lists.llvm.org/pipermail/cfe-dev/2020-April/065221.html
Signed-off-by: "Daniel P. Berrangé" <berrange@redhat.com>
Message-ID: <20240103123414.2401208-3-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
To quote wikipedia:
"Return-oriented programming (ROP) is a computer security exploit
technique that allows an attacker to execute code in the presence
of security defenses such as executable space protection and code
signing.
In this technique, an attacker gains control of the call stack to
hijack program control flow and then executes carefully chosen
machine instruction sequences that are already present in the
machine's memory, called "gadgets". Each gadget typically ends in
a return instruction and is located in a subroutine within the
existing program and/or shared library code. Chained together,
these gadgets allow an attacker to perform arbitrary operations
on a machine employing defenses that thwart simpler attacks."
QEMU is by no means perfect with an ever growing set of CVEs from
flawed hardware device emulation, which could potentially be
exploited using ROP techniques.
Since GCC 11 there has been a compiler option that can mitigate
against this exploit technique:
-fzero-call-user-regs
To understand it refer to these two resources:
https://www.jerkeby.se/newsletter/posts/rop-reduction-zero-call-user-regs/https://gcc.gnu.org/pipermail/gcc-patches/2020-August/552262.html
I used two programs to scan qemu-system-x86_64 for ROP gadgets:
https://github.com/0vercl0k/rphttps://github.com/JonathanSalwan/ROPgadget
When asked to find 8 byte gadgets, the 'rp' tool reports:
A total of 440278 gadgets found.
You decided to keep only the unique ones, 156143 unique gadgets found.
While the ROPgadget tool reports:
Unique gadgets found: 353122
With the --ropchain argument, the latter attempts to use the found
gadgets to product a chain that can execute arbitrary syscalls. With
current QEMU it succeeds in this task, which is an undesirable
situation.
With QEMU modified to use -fzero-call-user-regs=used-gpr the 'rp' tool
reports
A total of 528991 gadgets found.
You decided to keep only the unique ones, 121128 unique gadgets found.
This is 22% fewer unique gadgets
While the ROPgadget tool reports:
Unique gadgets found: 328605
This is 7% fewer unique gadgets. Crucially though, despite this more
modest reduction, the ROPgadget tool is no longer able to identify a
chain of gadgets for executing arbitrary syscalls. It fails at the
very first step, unable to find gadgets for populating registers for
a future syscall. Having said that, more advanced tools do still
manage to put together a viable ROP chain.
Also this only takes into account QEMU code. QEMU links to many 3rd
party shared libraries and ideally all of them would be compiled with
this same hardening. That becomes a distro policy question though.
In terms of performance impact, TCG was used as an evaluation test
case. We're not interested in protecting TCG since it isn't designed
to provide a security barrier, but it is performance sensitive code,
so useful as a guide to how other areas of QEMU might be impacted.
With the -fzero-call-user-regs=used-gpr argument present, using the
real world test of booting a linux kernel and having init immediately
poweroff, there is a ~1% slow down in performance under TCG. The QEMU
binary size also grows by approximately 1%.
By comparison, using the more aggressive -fzero-call-user-regs=all,
results in a slowdown of over 25% in TCG, which is clearly not an
acceptable impact, and a binary size increase of 5%.
Considering that 'used-gpr' successfully stopped ROPgadget assembling
a chain, this more targeted protection is a justifiable hardening
/ performance tradeoff.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: "Daniel P. Berrangé" <berrange@redhat.com>
Message-ID: <20240103123414.2401208-2-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The npcm7xx_watchdog_timer-test can take more than 60 seconds in
SPEED=slow mode on a loaded host system.
Bumping to 2 minutes will give more headroom.
Message-ID: <20240112164717.1063954-1-thuth@redhat.com>
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
The test_prescaler() part in the npcm7xx_watchdog_timer test is quite
repetitive, testing all possible combinations of the WTCLK and WTIS
bitfields. Since each test spins up a new instance of QEMU, this is
rather an expensive test, especially on loaded host systems.
For the normal quick test mode, it should be sufficient to test the
corner settings of these fields (i.e. 0 and 3), so we can speed up
this test in the default mode quite a bit.
Message-ID: <20240115070223.30178-1-thuth@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
When running with TCI, the boot-serial-test can take longer than 3 minutes:
https://gitlab.com/qemu-project/qemu/-/jobs/5890481086#L4774
Bump the timeout to 4 minutes to avoid CI failures here.
Message-ID: <20240115071146.31213-1-thuth@redhat.com>
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Solaris has #defines for htonll and ntohll which cause syntax errors
when compiling code that attempts to (re)define these functions..
Signed-off-by: Nick Briggs <nicholas.h.briggs@gmail.com>
Link: https://lore.kernel.org/r/65a04a7d.497ab3.3e7bef1f@gateway.sonic.net
Signed-off-by: Peter Xu <peterx@redhat.com>
Move it one layer down, so taking Virtio-migration as a feature for
migration.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-11-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Move it one layer down, so taking VFIO-migration as a feature for
migration.
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-10-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reorganize the page, moving things around, and add a few
headlines ("Postcopy internals", "Postcopy features") to cover sub-areas.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-9-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Split postcopy into a separate file. Introduce a head page "features.rst"
to keep all the features on top of migration framework.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Create an index page for migration module. Move VFIO migration there too.
A trivial touch-up on the title to use lower case there.
Since then we'll have "migration" as the top title, make the main doc file
renamed to "migration framework".
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Migration documentation is growing into a single file too large. Create a
sub-directory for it for a split.
We also already have separate vfio/virtio documentations, move it all over
into the directory.
Note that the virtio one is still not yet converted to rST. That is a job
for later.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240109064628.595453-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
We've found the source of flakiness in this test, so re-enable it.
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20230606144551.24367-4-farosas@suse.de
[peterx: rebase to 2a61a6964c, to use migration_test_add()]
Signed-off-by: Peter Xu <peterx@redhat.com>
Replace the tests registration with the new function that prints tests
names.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240104142144.9680-8-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Our usage of gtest results in us losing the very basic functionality
of "knowing which test failed". The issue is that gtest only prints
test names ("paths" in gtest parlance) once the test has finished, but
we use asserts in the tests and crash gtest itself before it can print
anything. We also use a final abort when the result of g_test_run is
not 0.
Depending on how the test failed/broke we can see the function that
trigged the abort, which may be representative of the test, but it
could also just be some generic function.
We have been relying on the primitive method of looking at the name of
the previous successful test and then looking at the code to figure
out which test should have come next.
Add a wrapper to the test registration that does the job of printing
the test name before running.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240104142144.9680-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
We're currently just asserting when incoming migration fails. Let's
print the error message from QMP as well.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240104142144.9680-6-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
