| Age | Commit message (Collapse) | Author | Files | Lines |
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Bail from kvm_recalculate_phys_map() and disable the optimized map if the
target vCPU's x2APIC ID is out-of-bounds, i.e. if the vCPU was added
and/or enabled its local APIC after the map was allocated. This fixes an
out-of-bounds access bug in the !x2apic_format path where KVM would write
beyond the end of phys_map.
Check the x2APIC ID regardless of whether or not x2APIC is enabled,
as KVM's hardcodes x2APIC ID to be the vCPU ID, i.e. it can't change, and
the map allocation in kvm_recalculate_apic_map() doesn't check for x2APIC
being enabled, i.e. the check won't get false postivies.
Note, this also affects the x2apic_format path, which previously just
ignored the "x2apic_id > new->max_apic_id" case. That too is arguably a
bug fix, as ignoring the vCPU meant that KVM would not send interrupts to
the vCPU until the next map recalculation. In practice, that "bug" is
likely benign as a newly present vCPU/APIC would immediately trigger a
recalc. But, there's no functional downside to disabling the map, and
a future patch will gracefully handle the -E2BIG case by retrying instead
of simply disabling the optimized map.
Opportunistically add a sanity check on the xAPIC ID size, along with a
comment explaining why the xAPIC ID is guaranteed to be "good".
Reported-by: Michal Luczaj <mhal@rbox.co>
Fixes: 5b84b0291702 ("KVM: x86: Honor architectural behavior for aliased 8-bit APIC IDs")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230602233250.1014316-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Increment vcpu->stat.exits when handling a fastpath VM-Exit without
going through any part of the "slow" path. Not bumping the exits stat
can result in wildly misleading exit counts, e.g. if the primary reason
the guest is exiting is to program the TSC deadline timer.
Fixes: 404d5d7bff0d ("KVM: X86: Introduce more exit_fastpath_completion enum values")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230602011920.787844-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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While testing Hyper-V enabled Windows Server 2019 guests on Zen4 hardware
I noticed that with vCPU count large enough (> 16) they sometimes froze at
boot.
With vCPU count of 64 they never booted successfully - suggesting some kind
of a race condition.
Since adding "vnmi=0" module parameter made these guests boot successfully
it was clear that the problem is most likely (v)NMI-related.
Running kvm-unit-tests quickly showed failing NMI-related tests cases, like
"multiple nmi" and "pending nmi" from apic-split, x2apic and xapic tests
and the NMI parts of eventinj test.
The issue was that once one NMI was being serviced no other NMI was allowed
to be set pending (NMI limit = 0), which was traced to
svm_is_vnmi_pending() wrongly testing for the "NMI blocked" flag rather
than for the "NMI pending" flag.
Fix this by testing for the right flag in svm_is_vnmi_pending().
Once this is done, the NMI-related kvm-unit-tests pass successfully and
the Windows guest no longer freezes at boot.
Fixes: fa4c027a7956 ("KVM: x86: Add support for SVM's Virtual NMI")
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/be4ca192eb0c1e69a210db3009ca984e6a54ae69.1684495380.git.maciej.szmigiero@oracle.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Factor in the address space (non-SMM vs. SMM) of the target shadow page
when recovering potential NX huge pages, otherwise KVM will retrieve the
wrong memslot when zapping shadow pages that were created for SMM. The
bug most visibly manifests as a WARN on the memslot being non-NULL, but
the worst case scenario is that KVM could unaccount the shadow page
without ensuring KVM won't install a huge page, i.e. if the non-SMM slot
is being dirty logged, but the SMM slot is not.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3911 at arch/x86/kvm/mmu/mmu.c:7015
kvm_nx_huge_page_recovery_worker+0x38c/0x3d0 [kvm]
CPU: 1 PID: 3911 Comm: kvm-nx-lpage-re
RIP: 0010:kvm_nx_huge_page_recovery_worker+0x38c/0x3d0 [kvm]
RSP: 0018:ffff99b284f0be68 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff99b284edd000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff9271397024e0 R08: 0000000000000000 R09: ffff927139702450
R10: 0000000000000000 R11: 0000000000000001 R12: ffff99b284f0be98
R13: 0000000000000000 R14: ffff9270991fcd80 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff927f9f640000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0aacad3ae0 CR3: 000000088fc2c005 CR4: 00000000003726e0
Call Trace:
<TASK>
__pfx_kvm_nx_huge_page_recovery_worker+0x10/0x10 [kvm]
kvm_vm_worker_thread+0x106/0x1c0 [kvm]
kthread+0xd9/0x100
ret_from_fork+0x2c/0x50
</TASK>
---[ end trace 0000000000000000 ]---
This bug was exposed by commit edbdb43fc96b ("KVM: x86: Preserve TDP MMU
roots until they are explicitly invalidated"), which allowed KVM to retain
SMM TDP MMU roots effectively indefinitely. Before commit edbdb43fc96b,
KVM would zap all SMM TDP MMU roots and thus all SMM TDP MMU shadow pages
once all vCPUs exited SMM, which made the window where this bug (recovering
an SMM NX huge page) could be encountered quite tiny. To hit the bug, the
NX recovery thread would have to run while at least one vCPU was in SMM.
Most VMs typically only use SMM during boot, and so the problematic shadow
pages were gone by the time the NX recovery thread ran.
Now that KVM preserves TDP MMU roots until they are explicitly invalidated
(e.g. by a memslot deletion), the window to trigger the bug is effectively
never closed because most VMMs don't delete memslots after boot (except
for a handful of special scenarios).
Fixes: eb298605705a ("KVM: x86/mmu: Do not recover dirty-tracked NX Huge Pages")
Reported-by: Fabio Coatti <fabio.coatti@gmail.com>
Closes: https://lore.kernel.org/all/CADpTngX9LESCdHVu_2mQkNGena_Ng2CphWNwsRGSMxzDsTjU2A@mail.gmail.com
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230602010137.784664-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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Add MSR_IA32_TSX_CTRL into msrs_to_save[] to explicitly tell userspace to
save/restore the register value during migration. Missing this may cause
userspace that relies on KVM ioctl(KVM_GET_MSR_INDEX_LIST) fail to port the
value to the target VM.
In addition, there is no need to add MSR_IA32_TSX_CTRL when
ARCH_CAP_TSX_CTRL_MSR is not supported in kvm_get_arch_capabilities(). So
add the checking in kvm_probe_msr_to_save().
Fixes: c11f83e0626b ("KVM: vmx: implement MSR_IA32_TSX_CTRL disable RTM functionality")
Reported-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20230509032348.1153070-1-mizhang@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Drop KVM's manipulation of guest's CPUID.0x12.1 ECX and EDX, i.e. the
allowed XFRM of SGX enclaves, now that KVM explicitly checks the guest's
allowed XCR0 when emulating ECREATE.
Note, this could theoretically break a setup where userspace advertises
a "bad" XFRM and relies on KVM to provide a sane CPUID model, but QEMU
is the only known user of KVM SGX, and QEMU explicitly sets the SGX CPUID
XFRM subleaf based on the guest's XCR0.
Reviewed-by: Kai Huang <kai.huang@intel.com>
Tested-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230503160838.3412617-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Explicitly check the vCPU's supported XCR0 when determining whether or not
the XFRM for ECREATE is valid. Checking CPUID works because KVM updates
guest CPUID.0x12.1 to restrict the leaf to a subset of the guest's allowed
XCR0, but that is rather subtle and KVM should not modify guest CPUID
except for modeling true runtime behavior (allowed XFRM is most definitely
not "runtime" behavior).
Reviewed-by: Kai Huang <kai.huang@intel.com>
Tested-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230503160838.3412617-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Include a definition of WARN_ON_ONCE() before using it.
Fixes: bb1fcc70d98f ("KVM: nVMX: Allow L1 to use 5-level page walks for nested EPT")
Cc: Sean Christopherson <seanjc@google.com>
Signed-off-by: Jacob Xu <jacobhxu@google.com>
[reworded commit message; changed <asm/bug.h> to <linux/bug.h>]
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220225012959.1554168-1-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 fixes for 6.4, take #1
- Plug a race in the stage-2 mapping code where the IPA and the PA
would end up being out of sync
- Make better use of the bitmap API (bitmap_zero, bitmap_zalloc...)
- FP/SVE/SME documentation update, in the hope that this field
becomes clearer...
- Add workaround for the usual Apple SEIS brokenness
- Random comment fixes
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git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
- Fix encoding of swp_entry due to added SWP_EXCLUSIVE flag
- Include reboot.h to avoid gcc-12 compiler warning
* tag 'parisc-for-6.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix encoding of swp_entry due to added SWP_EXCLUSIVE flag
parisc: kexec: include reboot.h
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Pull ARM fixes from Russell King:
- fix unwinder for uleb128 case
- fix kernel-doc warnings for HP Jornada 7xx
- fix unbalanced stack on vfp success path
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 9297/1: vfp: avoid unbalanced stack on 'success' return path
ARM: 9296/1: HP Jornada 7XX: fix kernel-doc warnings
ARM: 9295/1: unwind:fix unwind abort for uleb128 case
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Make sure the PEBS buffer is flushed before reprogramming the
hardware so that the correct record sizes are used
- Update the sample size for AMD BRS events
- Fix a confusion with using the same on-stack struct with different
events in the event processing path
* tag 'perf_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/ds: Flush PEBS DS when changing PEBS_DATA_CFG
perf/x86: Fix missing sample size update on AMD BRS
perf/core: Fix perf_sample_data not properly initialized for different swevents in perf_tp_event()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fix from Borislav Petkov:
- Add the required PCI IDs so that the generic SMN accesses provided by
amd_nb.c work for drivers which switch to them. Add a PCI device ID
to k10temp's table so that latter is loaded on such systems too
* tag 'x86_urgent_for_v6.4_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hwmon: (k10temp) Add PCI ID for family 19, model 78h
x86/amd_nb: Add PCI ID for family 19h model 78h
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Fix the __swp_offset() and __swp_entry() macros due to commit 6d239fc78c0b
("parisc/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE") which introduced the
SWP_EXCLUSIVE flag by reusing the _PAGE_ACCESSED flag.
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Fixes: 6d239fc78c0b ("parisc/mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE")
Cc: <stable@vger.kernel.org> # v6.3+
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SYM_FUNC_START_LOCAL_NOALIGN() adds an endbr leading to this layout
(leaving only the last 2 bytes of the address):
3bff <zen_untrain_ret>:
3bff: f3 0f 1e fa endbr64
3c03: f6 test $0xcc,%bl
3c04 <__x86_return_thunk>:
3c04: c3 ret
3c05: cc int3
3c06: 0f ae e8 lfence
However, "the RET at __x86_return_thunk must be on a 64 byte boundary,
for alignment within the BTB."
Use SYM_START instead.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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* kvm-arm64/pgtable-fixes-6.4:
: .
: Fixes for concurrent S2 mapping race from Oliver:
:
: "So it appears that there is a race between two parallel stage-2 map
: walkers that could lead to mapping the incorrect PA for a given IPA, as
: the IPA -> PA relationship picks up an unintended offset. This series
: eliminates the problem by using the current IPA of the walk as the
: source-of-truth regarding where we are in a map operation."
: .
KVM: arm64: Constify start/end/phys fields of the pgtable walker data
KVM: arm64: Infer PA offset from VA in hyp map walker
KVM: arm64: Infer the PA offset from IPA in stage-2 map walker
Signed-off-by: Marc Zyngier <maz@kernel.org>
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* kvm-arm64/misc-6.4:
: .
: Minor changes for 6.4:
:
: - Make better use of the bitmap API (bitmap_zero, bitmap_zalloc...)
:
: - FP/SVE/SME documentation update, in the hope that this field
: becomes clearer...
:
: - Add workaround for the usual Apple SEIS brokenness
:
: - Random comment fixes
: .
KVM: arm64: vgic: Add Apple M2 PRO/MAX cpus to the list of broken SEIS implementations
KVM: arm64: Clarify host SME state management
KVM: arm64: Restructure check for SVE support in FP trap handler
KVM: arm64: Document check for TIF_FOREIGN_FPSTATE
KVM: arm64: Fix repeated words in comments
KVM: arm64: Use the bitmap API to allocate bitmaps
KVM: arm64: Slightly optimize flush_context()
Signed-off-by: Marc Zyngier <maz@kernel.org>
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implementations
Unsurprisingly, the M2 PRO is also affected by the SEIS bug, so add it
to the naughty list. And since M2 MAX is likely to be of the same ilk,
flag it as well.
Tested on a M2 PRO mini machine.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Link: https://lore.kernel.org/r/20230501182141.39770-1-maz@kernel.org
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Commit c76c6c4ecbec0deb5 ("ARM: 9294/2: vfp: Fix broken softirq handling
with instrumentation enabled") updated the VFP exception entry logic to
go via a C function, so that we get the compiler's version of
local_bh_disable(), which may be instrumented, and isn't generally
callable from assembler.
However, this assumes that passing an alternative 'success' return
address works in C as it does in asm, and this is only the case if the C
calls in question are tail calls, as otherwise, the stack will need some
unwinding as well.
I have already sent patches to the list that replace most of the asm
logic with C code, and so it is preferable to have a minimal fix that
addresses the issue and can be backported along with the commit that it
fixes to v6.3 from v6.4. Hopefully, we can land the C conversion for v6.5.
So instead of passing the 'success' return address as a function
argument, pass the stack address from where to pop it so that both LR
and SP have the expected value.
Fixes: c76c6c4ecbec0deb5 ("ARM: 9294/2: vfp: Fix broken softirq handling with ...")
Reported-by: syzbot+d4b00edc2d0c910d4bf4@syzkaller.appspotmail.com
Tested-by: syzbot+d4b00edc2d0c910d4bf4@syzkaller.appspotmail.com
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
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kernel/pi gives rise to a lot of new sections that end up orphans: the
first attempt to fix that tried to enumerate them all in the linker
script, but kernel test robot with a random config keeps finding more of
them.
So prefix all those sections with .init.pi instead of only .init in
order to be able to easily catch them all in the linker script.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/oe-kbuild-all/202304301606.Cgp113Ha-lkp@intel.com/
Fixes: 26e7aacb83df ("riscv: Allow to downgrade paging mode from the command line")
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20230504120759.18730-1-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Include reboot.h in machine_kexec.c for declaration of
machine_crash_shutdown and machine_shutdown.
gcc-12 with W=1 reports:
arch/parisc/kernel/kexec.c:57:6: warning: no previous prototype for 'machine_crash_shutdown' [-Wmissing-prototypes]
57 | void machine_crash_shutdown(struct pt_regs *regs)
| ^~~~~~~~~~~~~~~~~~~~~~
arch/parisc/kernel/kexec.c:61:6: warning: no previous prototype for 'machine_shutdown' [-Wmissing-prototypes]
61 | void machine_shutdown(void)
| ^~~~~~~~~~~~~~~~
No functional changes intended.
Compile tested only.
Signed-off-by: Simon Horman <horms@kernel.org>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Helge Deller <deller@gmx.de>
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Commit
310e782a99c7 ("platform/x86/amd: pmc: Utilize SMN index 0 for driver probe")
switched to using amd_smn_read() which relies upon the misc PCI ID used
by DF function 3 being included in a table. The ID for model 78h is
missing in that table, so amd_smn_read() doesn't work.
Add the missing ID into amd_nb, restoring s2idle on this system.
[ bp: Simplify commit message. ]
Fixes: 310e782a99c7 ("platform/x86/amd: pmc: Utilize SMN index 0 for driver probe")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # pci_ids.h
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230427053338.16653-2-mario.limonciello@amd.com
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Several similar kernel warnings can be triggered,
[56605.607840] CPU0 PEBS record size 0, expected 32, config 0 cpuc->record_size=208
when the below commands are running in parallel for a while on SPR.
while true;
do
perf record --no-buildid -a --intr-regs=AX \
-e cpu/event=0xd0,umask=0x81/pp \
-c 10003 -o /dev/null ./triad;
done &
while true;
do
perf record -o /tmp/out -W -d \
-e '{ld_blocks.store_forward:period=1000000, \
MEM_TRANS_RETIRED.LOAD_LATENCY:u:precise=2:ldlat=4}' \
-c 1037 ./triad;
done
The triad program is just the generation of loads/stores.
The warnings are triggered when an unexpected PEBS record (with a
different config and size) is found.
A system-wide PEBS event with the large PEBS config may be enabled
during a context switch. Some PEBS records for the system-wide PEBS
may be generated while the old task is sched out but the new one
hasn't been sched in yet. When the new task is sched in, the
cpuc->pebs_record_size may be updated for the per-task PEBS events. So
the existing system-wide PEBS records have a different size from the
later PEBS records.
The PEBS buffer should be flushed right before the hardware is
reprogrammed. The new size and threshold should be updated after the
old buffer has been flushed.
Reported-by: Stephane Eranian <eranian@google.com>
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230421184529.3320912-1-kan.liang@linux.intel.com
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It missed to convert a PERF_SAMPLE_BRANCH_STACK user to call the new
perf_sample_save_brstack() helper in order to update the dyn_size.
This affects AMD Zen3 machines with the branch-brs event.
Fixes: eb55b455ef9c ("perf/core: Add perf_sample_save_brstack() helper")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20230427030527.580841-1-namhyung@kernel.org
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Commit 0da6e5fd6c37 ("gcc: disable '-Warray-bounds' for gcc-13 too") makes
config GCC11_NO_ARRAY_BOUNDS to be for disabling -Warray-bounds in any gcc
version 11 and upwards, and with that, removes the GCC12_NO_ARRAY_BOUNDS
config as it is now covered by the semantics of GCC11_NO_ARRAY_BOUNDS.
As GCC11_NO_ARRAY_BOUNDS is yes by default, there is no need for the s390
architecture to explicitly select GCC11_NO_ARRAY_BOUNDS. Hence, the select
GCC12_NO_ARRAY_BOUNDS in arch/s390/Kconfig can simply be dropped.
Remove the unneeded "select GCC12_NO_ARRAY_BOUNDS".
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- Introduce local{,64}_try_cmpxchg() - a slightly more optimal
primitive, which will be used in perf events ring-buffer code
- Simplify/modify rwsems on PREEMPT_RT, to address writer starvation
- Misc cleanups/fixes
* tag 'locking-core-2023-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomic: Correct (cmp)xchg() instrumentation
locking/x86: Define arch_try_cmpxchg_local()
locking/arch: Wire up local_try_cmpxchg()
locking/generic: Wire up local{,64}_try_cmpxchg()
locking/atomic: Add generic try_cmpxchg{,64}_local() support
locking/rwbase: Mitigate indefinite writer starvation
locking/arch: Rename all internal __xchg() names to __arch_xchg()
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Merge my x86 uaccess updates branch.
The LAM ("Linear Address Masking") updates in this release made me
unhappy about how "access_ok()" was done, and it actually turned out to
have a couple of small bugs in it too. This is my cleanup of the code:
- use the sign bit of the __user pointer rather than masking the
address and checking it against the TASK_SIZE range.
We already did this part for the get/put_user() side, but
'access_ok()' did the naïve "mask and range check" thing, which not
only generates nasty code, but also ended up meaning that __access_ok
itself didn't do a good job, and so copy_from_user_nmi() didn't get
the check right.
- move all the code that is 64-bit only into the 64-bit version of the
header file, so that we don't unnecessarily pollute the shared x86
code and make it look like LAM might work in 32-bit too.
- fix a bug in the address masking (that doesn't end up mattering: in
this case the fix was to just remove the buggy code entirely).
- a couple of trivial cleanups and added commentary about the
access_ok() rules.
* x86-uaccess-cleanup:
x86-64: mm: clarify the 'positive addresses' user address rules
x86: mm: remove 'sign' games from LAM untagged_addr*() macros
x86: uaccess: move 32-bit and 64-bit parts into proper <asm/uaccess_N.h> header
x86: mm: remove architecture-specific 'access_ok()' define
x86-64: make access_ok() independent of LAM
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git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull more RISC-V updates from Palmer Dabbelt:
- Support for hibernation
- The .rela.dyn section has been moved to the init area
- A fix for the SBI probing to allow for implementation-defined
behavior
- Various other fixes and cleanups throughout the tree
* tag 'riscv-for-linus-6.4-mw2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
RISC-V: include cpufeature.h in cpufeature.c
riscv: Move .rela.dyn to the init sections
dt-bindings: riscv: explicitly mention assumption of Zicsr & Zifencei support
riscv: compat_syscall_table: Fixup compile warning
RISC-V: fixup in-flight collision with ARCH_WANT_OPTIMIZE_VMEMMAP rename
RISC-V: fix sifive and thead section mismatches in errata
RISC-V: Align SBI probe implementation with spec
riscv: mm: remove redundant parameter of create_fdt_early_page_table
riscv: Adjust dependencies of HAVE_DYNAMIC_FTRACE selection
RISC-V: Add arch functions to support hibernation/suspend-to-disk
RISC-V: mm: Enable huge page support to kernel_page_present() function
RISC-V: Factor out common code of __cpu_resume_enter()
RISC-V: Change suspend_save_csrs and suspend_restore_csrs to public function
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Pull more kvm updates from Paolo Bonzini:
"This includes the 6.4 changes for RISC-V, and a few bugfix patches for
other architectures. For x86, this closes a longstanding performance
issue in the newer and (usually) more scalable page table management
code.
RISC-V:
- ONE_REG interface to enable/disable SBI extensions
- Zbb extension for Guest/VM
- AIA CSR virtualization
x86:
- Fix a long-standing TDP MMU flaw, where unloading roots on a vCPU
can result in the root being freed even though the root is
completely valid and can be reused as-is (with a TLB flush).
s390:
- A couple of bugfixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: s390: fix race in gmap_make_secure()
KVM: s390: pv: fix asynchronous teardown for small VMs
KVM: x86: Preserve TDP MMU roots until they are explicitly invalidated
RISC-V: KVM: Virtualize per-HART AIA CSRs
RISC-V: KVM: Use bitmap for irqs_pending and irqs_pending_mask
RISC-V: KVM: Add ONE_REG interface for AIA CSRs
RISC-V: KVM: Implement subtype for CSR ONE_REG interface
RISC-V: KVM: Initial skeletal support for AIA
RISC-V: KVM: Drop the _MASK suffix from hgatp.VMID mask defines
RISC-V: Detect AIA CSRs from ISA string
RISC-V: Add AIA related CSR defines
RISC-V: KVM: Allow Zbb extension for Guest/VM
RISC-V: KVM: Add ONE_REG interface to enable/disable SBI extensions
RISC-V: KVM: Alphabetize selects
KVM: RISC-V: Retry fault if vma_lookup() results become invalid
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https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
For 6.4
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Fix a long-standing flaw in x86's TDP MMU where unloading roots on a vCPU can
result in the root being freed even though the root is completely valid and
can be reused as-is (with a TLB flush).
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KVM/riscv changes for 6.4
- ONE_REG interface to enable/disable SBI extensions
- Zbb extension for Guest/VM
- AIA CSR virtualization
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Fix kernel-doc warnings from the kernel test robot:
jornada720_ssp.c:24: warning: Function parameter or member 'jornada_ssp_lock' not described in 'DEFINE_SPINLOCK'
jornada720_ssp.c:24: warning: expecting prototype for arch/arm/mac(). Prototype was for DEFINE_SPINLOCK() instead
jornada720_ssp.c:34: warning: Function parameter or member 'byte' not described in 'jornada_ssp_reverse'
jornada720_ssp.c:57: warning: Function parameter or member 'byte' not described in 'jornada_ssp_byte'
jornada720_ssp.c:85: warning: Function parameter or member 'byte' not described in 'jornada_ssp_inout'
Link: lore.kernel.org/r/202304210535.tWby3jWF-lkp@intel.com
Fixes: 69ebb22277a5 ("[ARM] 4506/1: HP Jornada 7XX: Addition of SSP Platform Driver")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kristoffer Ericson <Kristoffer.ericson@gmail.com>
Cc: patches@armlinux.org.uk
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
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When unwind instruction is 0xb2,the subsequent instructions
are uleb128 bytes.
For now,it uses only the first uleb128 byte in code.
For vsp increments of 0x204~0x400,use one uleb128 byte like below:
0xc06a00e4 <unwind_test_work>: 0x80b27fac
Compact model index: 0
0xb2 0x7f vsp = vsp + 1024
0xac pop {r4, r5, r6, r7, r8, r14}
For vsp increments larger than 0x400,use two uleb128 bytes like below:
0xc06a00e4 <unwind_test_work>: @0xc0cc9e0c
Compact model index: 1
0xb2 0x81 0x01 vsp = vsp + 1032
0xac pop {r4, r5, r6, r7, r8, r14}
The unwind works well since the decoded uleb128 byte is also 0x81.
For vsp increments larger than 0x600,use two uleb128 bytes like below:
0xc06a00e4 <unwind_test_work>: @0xc0cc9e0c
Compact model index: 1
0xb2 0x81 0x02 vsp = vsp + 1544
0xac pop {r4, r5, r6, r7, r8, r14}
In this case,the decoded uleb128 result is 0x101(vsp=0x204+(0x101<<2)).
While the uleb128 used in code is 0x81(vsp=0x204+(0x81<<2)).
The unwind aborts at this frame since it gets incorrect vsp.
To fix this,add uleb128 decode to cover all the above case.
Signed-off-by: Haibo Li <haibo.li@mediatek.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
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git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull more MM updates from Andrew Morton:
- Some DAMON cleanups from Kefeng Wang
- Some KSM work from David Hildenbrand, to make the PR_SET_MEMORY_MERGE
ioctl's behavior more similar to KSM's behavior.
[ Andrew called these "final", but I suspect we'll have a series fixing
up the fact that the last commit in the dmapools series in the
previous pull seems to have unintentionally just reverted all the
other commits in the same series.. - Linus ]
* tag 'mm-stable-2023-05-03-16-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
mm: hwpoison: coredump: support recovery from dump_user_range()
mm/page_alloc: add some comments to explain the possible hole in __pageblock_pfn_to_page()
mm/ksm: move disabling KSM from s390/gmap code to KSM code
selftests/ksm: ksm_functional_tests: add prctl unmerge test
mm/ksm: unmerge and clear VM_MERGEABLE when setting PR_SET_MEMORY_MERGE=0
mm/damon/paddr: fix missing folio_sz update in damon_pa_young()
mm/damon/paddr: minor refactor of damon_pa_mark_accessed_or_deactivate()
mm/damon/paddr: minor refactor of damon_pa_pageout()
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git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"A few arm64 fixes that came in during the merge window for -rc1.
The main thing is restoring the pointer authentication hwcaps, which
disappeared during some recent refactoring
- Fix regression in CPU erratum workaround when disabling the MMU
- Fix detection of pointer authentication hwcaps
- Avoid writeable, executable ELF sections in vmlinux"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: lds: move .got section out of .text
arm64: kernel: remove SHF_WRITE|SHF_EXECINSTR from .idmap.text
arm64: cpufeature: Fix pointer auth hwcaps
arm64: Fix label placement in record_mmu_state()
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git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson
Pull LoongArch updates from Huacai Chen:
- Better backtraces for humanization
- Relay BCE exceptions to userland as SIGSEGV
- Provide kernel fpu functions
- Optimize memory ops (memset/memcpy/memmove)
- Optimize checksum and crc32(c) calculation
- Add ARCH_HAS_FORTIFY_SOURCE selection
- Add function error injection support
- Add ftrace with direct call support
- Add basic perf tools support
* tag 'loongarch-6.4' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (24 commits)
tools/perf: Add basic support for LoongArch
LoongArch: ftrace: Add direct call trampoline samples support
LoongArch: ftrace: Add direct call support
LoongArch: ftrace: Implement ftrace_find_callable_addr() to simplify code
LoongArch: ftrace: Fix build error if DYNAMIC_FTRACE_WITH_REGS is not set
LoongArch: ftrace: Abstract DYNAMIC_FTRACE_WITH_ARGS accesses
LoongArch: Add support for function error injection
LoongArch: Add ARCH_HAS_FORTIFY_SOURCE selection
LoongArch: crypto: Add crc32 and crc32c hw acceleration
LoongArch: Add checksum optimization for 64-bit system
LoongArch: Optimize memory ops (memset/memcpy/memmove)
LoongArch: Provide kernel fpu functions
LoongArch: Relay BCE exceptions to userland as SIGSEGV with si_code=SEGV_BNDERR
LoongArch: Tweak the BADV and CPUCFG.PRID lines in show_regs()
LoongArch: Humanize the ESTAT line when showing registers
LoongArch: Humanize the ECFG line when showing registers
LoongArch: Humanize the EUEN line when showing registers
LoongArch: Humanize the PRMD line when showing registers
LoongArch: Humanize the CRMD line when showing registers
LoongArch: Fix format of CSR lines during show_regs()
...
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Pull arch/csky updates from Guo Ren:
- Remove CPU_TLB_SIZE config
- Prevent spurious page faults
* tag 'csky-for-linus-6.4' of https://github.com/c-sky/csky-linux:
csky: mmu: Prevent spurious page faults
csky: remove obsolete config CPU_TLB_SIZE
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Fix a potential race in gmap_make_secure() and remove the last user of
follow_page() without FOLL_GET.
The old code is locking something it doesn't have a reference to, and
as explained by Jason and David in this discussion:
https://lore.kernel.org/linux-mm/Y9J4P%2FRNvY1Ztn0Q@nvidia.com/
it can lead to all kind of bad things, including the page getting
unmapped (MADV_DONTNEED), freed, reallocated as a larger folio and the
unlock_page() would target the wrong bit.
There is also another race with the FOLL_WRITE, which could race
between the follow_page() and the get_locked_pte().
The main point is to remove the last use of follow_page() without
FOLL_GET or FOLL_PIN, removing the races can be considered a nice
bonus.
Link: https://lore.kernel.org/linux-mm/Y9J4P%2FRNvY1Ztn0Q@nvidia.com/
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Fixes: 214d9bbcd3a6 ("s390/mm: provide memory management functions for protected KVM guests")
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20230428092753.27913-2-imbrenda@linux.ibm.com>
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On machines without the Destroy Secure Configuration Fast UVC, the
topmost level of page tables is set aside and freed asynchronously
as last step of the asynchronous teardown.
Each gmap has a host_to_guest radix tree mapping host (userspace)
addresses (with 1M granularity) to gmap segment table entries (pmds).
If a guest is smaller than 2GB, the topmost level of page tables is the
segment table (i.e. there are only 2 levels). Replacing it means that
the pointers in the host_to_guest mapping would become stale and cause
all kinds of nasty issues.
This patch fixes the issue by disallowing asynchronous teardown for
guests with only 2 levels of page tables. Userspace should (and already
does) try using the normal destroy if the asynchronous one fails.
Update s390_replace_asce so it refuses to replace segment type ASCEs.
This is still needed in case the normal destroy VM fails.
Fixes: fb491d5500a7 ("KVM: s390: pv: asynchronous destroy for reboot")
Reviewed-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Message-Id: <20230421085036.52511-2-imbrenda@linux.ibm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:
"Two important fixes in here:
- The argument pointer register was wrong when calling 64-bit
firmware functions, which may cause random memory corruption or
crashes.
- Ensure page alignment in cache flush functions, otherwise not all
memory might get flushed.
The rest are cleanups (mmap implementation, panic path) and usual
smaller updates.
Summary:
- Calculate correct argument pointer in real64_call_asm()
- Cleanup mmap implementation regarding color alignment (John David
Anglin)
- Spinlock fixes in panic path (Guilherme G. Piccoli)
- build doc update for parisc64 (Randy Dunlap)
- Ensure page alignment in flush functions"
* tag 'parisc-for-6.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix argument pointer in real64_call_asm()
parisc: Cleanup mmap implementation regarding color alignment
parisc: Drop HP-UX constants and structs from grfioctl.h
parisc: Ensure page alignment in flush functions
parisc: Replace regular spinlock with spin_trylock on panic path
parisc: update kbuild doc. aliases for parisc64
parisc: Limit amount of kgdb breakpoints on parisc
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git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux
Pull uml updates from Richard Weinberger:
- Make stub data pages configurable
- Make it harder to mix user and kernel code by accident
* tag 'uml-for-linus-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/uml/linux:
um: make stub data pages size tweakable
um: prevent user code in modules
um: further clean up user_syms
um: don't export printf()
um: hostfs: define our own API boundary
um: add __weak for exported functions
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git://git.kernel.org/pub/scm/linux/kernel/git/pateldipen1984/linux
Pull hardware timestamp engine updates from Dipen Patel:
"The changes for the hte subsystem include:
- Add Tegra234 HTE provider and relevant DT bindings
- Update MAINTAINERS file for the HTE subsystem"
* tag 'for-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/pateldipen1984/linux:
hte: tegra-194: Use proper includes
hte: Use device_match_of_node()
hte: tegra-194: Fix off by one in tegra_hte_map_to_line_id()
hte: tegra: fix 'struct of_device_id' build error
hte: Use of_property_present() for testing DT property presence
gpio: tegra186: Add Tegra234 hte support
hte: handle nvidia,gpio-controller property
hte: Deprecate nvidia,slices property
hte: Add Tegra234 provider
hte: Re-phrase tegra API document
arm64: tegra: Add Tegra234 GTE nodes
dt-bindings: timestamp: Deprecate nvidia,slices property
dt-bindings: timestamp: Add Tegra234 support
MAINTAINERS: Add HTE/timestamp subsystem details
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Dave Hansen found the "(long) addr >= 0" code in the x86-64 access_ok
checks somewhat confusing, and suggested using a helper to clarify what
the code is doing.
So this does exactly that: clarifying what the sign bit check is all
about, by adding a helper macro that makes it clear what it is testing.
This also adds some explicit comments talking about how even with LAM
enabled, any addresses with the sign bit will still GP-fault in the
non-canonical region just above the sign bit.
This is all what allows us to do the user address checks with just the
sign bit, and furthermore be a bit cavalier about accesses that might be
done with an additional offset even past that point.
(And yes, this talks about 'positive' even though zero is also a valid
user address and so technically we should call them 'non-negative'. But
I don't think using 'non-negative' ends up being more understandable).
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The intent of the sign games was to not modify kernel addresses when
untagging them. However, that had two issues:
(a) it didn't actually work as intended, since the mask was calculated
as 'addr >> 63' on an _unsigned_ address. So instead of getting a
mask of all ones for kernel addresses, you just got '1'.
(b) untagging a kernel address isn't actually a valid operation anyway.
Now, (a) had originally been true for both 'untagged_addr()' and the
remote version of it, but had accidentally been fixed for the regular
version of untagged_addr() by commit e0bddc19ba95 ("x86/mm: Reduce
untagged_addr() overhead for systems without LAM"). That one rewrote
the shift to be part of the alternative asm code, and in the process
changed the unsigned shift into a signed 'sar' instruction.
And while it is true that we don't want to turn what looks like a kernel
address into a user address by masking off the high bit, that doesn't
need these sign masking games - all it needs is that the mm context
'untag_mask' value has the high bit set.
Which it always does.
So simplify the code by just removing the superfluous (and in the case
of untagged_addr_remote(), still buggy) sign bit games in the address
masking.
Acked-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The x86 <asm/uaccess.h> file has grown features that are specific to
x86-64 like LAM support and the related access_ok() changes. They
really should be in the <asm/uaccess_64.h> file and not pollute the
generic x86 header.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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There's already a generic definition of 'access_ok()' in the
asm-generic/access_ok.h header file, and the only difference bwteen that
and the x86-specific one is the added check for WARN_ON_IN_IRQ().
And it turns out that the reason for that check is long gone: it used to
use a "user_addr_max()" inline function that depended on the current
thread, and caused problems in non-thread contexts.
For details, see commits 7c4788950ba5 ("x86/uaccess, sched/preempt:
Verify access_ok() context") and in particular commit ae31fe51a3cc
("perf/x86: Restore TASK_SIZE check on frame pointer") about how and why
this came to be.
But that "current task" issue was removed in the big set_fs() removal by
Christoph Hellwig in commit 47058bb54b57 ("x86: remove address space
overrides using set_fs()").
So the reason for the test and the architecture-specific access_ok()
define no longer exists, and is actually harmful these days. For
example, it led various 'copy_from_user_nmi()' games (eg using
__range_not_ok() instead, and then later converted to __access_ok() when
that became ok).
And that in turn meant that LAM was broken for the frame following
before this series, because __access_ok() used to not do the address
untagging.
Accessing user state still needs care in many contexts, but access_ok()
is not the place for this test.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds torvalds@linux-foundation.org>
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The linear address masking (LAM) code made access_ok() more complicated,
in that it now needs to untag the address in order to verify the access
range. See commit 74c228d20a51 ("x86/uaccess: Provide untagged_addr()
and remove tags before address check").
We were able to avoid that overhead in the get_user/put_user code paths
by simply using the sign bit for the address check, and depending on the
GP fault if the address was non-canonical, which made it all independent
of LAM.
And we can do the same thing for access_ok(): simply check that the user
pointer range has the high bit clear. No need to bother with any
address bit masking.
In fact, we can go a bit further, and just check the starting address
for known small accesses ranges: any accesses that overflow will still
be in the non-canonical area and will still GP fault.
To still make syzkaller catch any potentially unchecked user addresses,
we'll continue to warn about GP faults that are caused by accesses in
the non-canonical range. But we'll limit that to purely "high bit set
and past the one-page 'slop' area".
We could probably just do that "check only starting address" for any
arbitrary range size: realistically all kernel accesses to user space
will be done starting at the low address. But let's leave that kind of
optimization for later. As it is, this already allows us to generate
simpler code and not worry about any tag bits in the address.
The one thing to look out for is the GUP address check: instead of
actually copying data in the virtual address range (and thus bad
addresses being caught by the GP fault), GUP will look up the page
tables manually. As a result, the page table limits need to be checked,
and that was previously implicitly done by the access_ok().
With the relaxed access_ok() check, we need to just do an explicit check
for TASK_SIZE_MAX in the GUP code instead. The GUP code already needs
to do the tag bit unmasking anyway, so there this is all very
straightforward, and there are no LAM issues.
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Fix the argument pointer (ap) to point to real-mode memory
instead of virtual memory.
It's interesting that this issue hasn't shown up earlier, as this could
have happened with any 64-bit PDC ROM code.
I just noticed it because I suddenly faced a HPMC while trying to execute
the 64-bit STI ROM code of an Visualize-FXe graphics card for the STI
text console.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
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This change simplifies the randomization of file mapping regions. It
reworks the code to remove duplication. The flow is now similar to
that for mips. Finally, we consistently use the do_color_align variable
to determine when color alignment is needed.
Tested on rp3440.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
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