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[ Upstream commit 077b7320942b64b0da182aefd83c374462a65535 ]
The function names init_registers() and restore_registers() are used
in several net/ethernet/ and gpu/drm/ drivers for other purposes (not
calls to UML functions), so rename them.
This fixes multiple build errors.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Cc: linux-um@lists.infradead.org
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b4813539d37fa31fed62cdfab7bd2dd8929c5b2e ]
It is called by the #MC handler which is noinstr.
Fixes
vmlinux.o: warning: objtool: do_machine_check()+0xbd6: call to memset() leaves .noinstr.text section
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211208111343.8130-9-bp@alien8.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3c7ce80a818fa7950be123cac80cd078e5ac1013 ]
And allow instrumentation inside it because it does calls to other
facilities which will not be tagged noinstr.
Fixes
vmlinux.o: warning: objtool: do_machine_check()+0xc73: call to mce_panic() leaves .noinstr.text section
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211208111343.8130-8-bp@alien8.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 71d5049b053876afbde6c3273250b76935494ab2 ]
Move the switching code into a function so that it can be re-used and
add a global TLB flush. This makes sure that usage of memory which is
not mapped in the trampoline page-table is reliably caught.
Also move the clearing of CR4.PCIDE before the CR3 switch because the
cr4_clear_bits() function will access data not mapped into the
trampoline page-table.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211202153226.22946-4-joro@8bytes.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit de768416b203ac84e02a757b782a32efb388476f ]
A contrived zero-length write, for example, by using write(2):
...
ret = write(fd, str, 0);
...
to the "flags" file causes:
BUG: KASAN: stack-out-of-bounds in flags_write
Write of size 1 at addr ffff888019be7ddf by task writefile/3787
CPU: 4 PID: 3787 Comm: writefile Not tainted 5.16.0-rc7+ #12
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
due to accessing buf one char before its start.
Prevent such out-of-bounds access.
[ bp: Productize into a proper patch. Link below is the next best
thing because the original mail didn't get archived on lore. ]
Fixes: 0451d14d0561 ("EDAC, mce_amd_inj: Modify flags attribute to use string arguments")
Signed-off-by: Zhang Zixun <zhang133010@icloud.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/linux-edac/YcnePfF1OOqoQwrX@zn.tnic/
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9c494ca4d3a535f9ca11ad6af1813983c1c6cbdd upstream.
"Stolen memory" is memory set aside for use by an Intel integrated GPU.
The intel_graphics_quirks() early quirk reserves this memory when it is
called for a GPU that appears in the intel_early_ids[] table of integrated
GPUs.
Previously intel_graphics_quirks() was marked as QFLAG_APPLY_ONCE, so it
was called only for the first Intel GPU found. If a discrete GPU happened
to be enumerated first, intel_graphics_quirks() was called for it but not
for any integrated GPU found later. Therefore, stolen memory for such an
integrated GPU was never reserved.
For example, this problem occurs in this Alderlake-P (integrated) + DG2
(discrete) topology where the DG2 is found first, but stolen memory is
associated with the integrated GPU:
- 00:01.0 Bridge
`- 03:00.0 DG2 discrete GPU
- 00:02.0 Integrated GPU (with stolen memory)
Remove the QFLAG_APPLY_ONCE flag and call intel_graphics_quirks() for every
Intel GPU. Reserve stolen memory for the first GPU that appears in
intel_early_ids[].
[bhelgaas: commit log, add code comment, squash in
https://lore.kernel.org/r/20220118190558.2ququ4vdfjuahicm@ldmartin-desk2]
Link: https://lore.kernel.org/r/20220114002843.2083382-1-lucas.demarchi@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9fb12fe5b93b94b9e607509ba461e17f4cc6a264 upstream.
The fixed counter 3 is used for the Topdown metrics, which hasn't been
enabled for KVM guests. Userspace accessing to it will fail as it's not
included in get_fixed_pmc(). This breaks KVM selftests on ICX+ machines,
which have this counter.
To reproduce it on ICX+ machines, ./state_test reports:
==== Test Assertion Failure ====
lib/x86_64/processor.c:1078: r == nmsrs
pid=4564 tid=4564 - Argument list too long
1 0x000000000040b1b9: vcpu_save_state at processor.c:1077
2 0x0000000000402478: main at state_test.c:209 (discriminator 6)
3 0x00007fbe21ed5f92: ?? ??:0
4 0x000000000040264d: _start at ??:?
Unexpected result from KVM_GET_MSRS, r: 17 (failed MSR was 0x30c)
With this patch, it works well.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Message-Id: <20211217124934.32893-1-wei.w.wang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: e2ada66ec418 ("kvm: x86: Add Intel PMU MSRs to msrs_to_save[]")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ff083a2d972f56bebfd82409ca62e5dfce950961 upstream.
Protect perf_guest_cbs with RCU to fix multiple possible errors. Luckily,
all paths that read perf_guest_cbs already require RCU protection, e.g. to
protect the callback chains, so only the direct perf_guest_cbs touchpoints
need to be modified.
Bug #1 is a simple lack of WRITE_ONCE/READ_ONCE behavior to ensure
perf_guest_cbs isn't reloaded between a !NULL check and a dereference.
Fixed via the READ_ONCE() in rcu_dereference().
Bug #2 is that on weakly-ordered architectures, updates to the callbacks
themselves are not guaranteed to be visible before the pointer is made
visible to readers. Fixed by the smp_store_release() in
rcu_assign_pointer() when the new pointer is non-NULL.
Bug #3 is that, because the callbacks are global, it's possible for
readers to run in parallel with an unregisters, and thus a module
implementing the callbacks can be unloaded while readers are in flight,
resulting in a use-after-free. Fixed by a synchronize_rcu() call when
unregistering callbacks.
Bug #1 escaped notice because it's extremely unlikely a compiler will
reload perf_guest_cbs in this sequence. perf_guest_cbs does get reloaded
for future derefs, e.g. for ->is_user_mode(), but the ->is_in_guest()
guard all but guarantees the consumer will win the race, e.g. to nullify
perf_guest_cbs, KVM has to completely exit the guest and teardown down
all VMs before KVM start its module unload / unregister sequence. This
also makes it all but impossible to encounter bug #3.
Bug #2 has not been a problem because all architectures that register
callbacks are strongly ordered and/or have a static set of callbacks.
But with help, unloading kvm_intel can trigger bug #1 e.g. wrapping
perf_guest_cbs with READ_ONCE in perf_misc_flags() while spamming
kvm_intel module load/unload leads to:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP
CPU: 6 PID: 1825 Comm: stress Not tainted 5.14.0-rc2+ #459
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:perf_misc_flags+0x1c/0x70
Call Trace:
perf_prepare_sample+0x53/0x6b0
perf_event_output_forward+0x67/0x160
__perf_event_overflow+0x52/0xf0
handle_pmi_common+0x207/0x300
intel_pmu_handle_irq+0xcf/0x410
perf_event_nmi_handler+0x28/0x50
nmi_handle+0xc7/0x260
default_do_nmi+0x6b/0x170
exc_nmi+0x103/0x130
asm_exc_nmi+0x76/0xbf
Fixes: 39447b386c84 ("perf: Enhance perf to allow for guest statistic collection from host")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211111020738.2512932-2-seanjc@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 57690554abe135fee81d6ac33cc94d75a7e224bb upstream.
Both __pkru_allows_write() and arch_set_user_pkey_access() shift
PKRU_WD_BIT (a signed constant) by up to 30 bits, hitting the
sign bit.
Use unsigned constants instead.
Clearly pkey 15 has not been used in combination with UBSAN yet.
Noticed by code inspection only. I can't actually provoke the
compiler into generating incorrect logic as far as this shift is
concerned.
[
dhansen: add stable@ tag, plus minor changelog massaging,
For anyone doing backports, these #defines were in
arch/x86/include/asm/pgtable.h before 784a46618f6.
]
Fixes: 33a709b25a76 ("mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20211216000856.4480-1-andrew.cooper3@citrix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3244867af8c065e51969f1bffe732d3ebfd9a7d2 upstream.
Do not bail early if there are no bits set in the sparse banks for a
non-sparse, a.k.a. "all CPUs", IPI request. Per the Hyper-V spec, it is
legal to have a variable length of '0', e.g. VP_SET's BankContents in
this case, if the request can be serviced without the extra info.
It is possible that for a given invocation of a hypercall that does
accept variable sized input headers that all the header input fits
entirely within the fixed size header. In such cases the variable sized
input header is zero-sized and the corresponding bits in the hypercall
input should be set to zero.
Bailing early results in KVM failing to send IPIs to all CPUs as expected
by the guest.
Fixes: 214ff83d4473 ("KVM: x86: hyperv: implement PV IPI send hypercalls")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211207220926.718794-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1ff2fc02862d52e18fd3daabcfe840ec27e920a8 upstream.
Reserving memory using efi_mem_reserve() calls into the x86
efi_arch_mem_reserve() function. This function will insert a new EFI
memory descriptor into the EFI memory map representing the area of
memory to be reserved and marking it as EFI runtime memory. As part
of adding this new entry, a new EFI memory map is allocated and mapped.
The mapping is where a problem can occur. This new memory map is mapped
using early_memremap() and generally mapped encrypted, unless the new
memory for the mapping happens to come from an area of memory that is
marked as EFI_BOOT_SERVICES_DATA memory. In this case, the new memory will
be mapped unencrypted. However, during replacement of the old memory map,
efi_mem_type() is disabled, so the new memory map will now be long-term
mapped encrypted (in efi.memmap), resulting in the map containing invalid
data and causing the kernel boot to crash.
Since it is known that the area will be mapped encrypted going forward,
explicitly map the new memory map as encrypted using early_memremap_prot().
Cc: <stable@vger.kernel.org> # 4.14.x
Fixes: 8f716c9b5feb ("x86/mm: Add support to access boot related data in the clear")
Link: https://lore.kernel.org/all/ebf1eb2940405438a09d51d121ec0d02c8755558.1634752931.git.thomas.lendacky@amd.com/
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
[ardb: incorporate Kconfig fix by Arnd]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 51523ed1c26758de1af7e58730a656875f72f783 upstream.
The trampoline_pgd only maps the 0xfffffff000000000-0xffffffffffffffff
range of kernel memory (with 4-level paging). This range contains the
kernel's text+data+bss mappings and the module mapping space but not the
direct mapping and the vmalloc area.
This is enough to get the application processors out of real-mode, but
for code that switches back to real-mode the trampoline_pgd is missing
important parts of the address space. For example, consider this code
from arch/x86/kernel/reboot.c, function machine_real_restart() for a
64-bit kernel:
#ifdef CONFIG_X86_32
load_cr3(initial_page_table);
#else
write_cr3(real_mode_header->trampoline_pgd);
/* Exiting long mode will fail if CR4.PCIDE is set. */
if (boot_cpu_has(X86_FEATURE_PCID))
cr4_clear_bits(X86_CR4_PCIDE);
#endif
/* Jump to the identity-mapped low memory code */
#ifdef CONFIG_X86_32
asm volatile("jmpl *%0" : :
"rm" (real_mode_header->machine_real_restart_asm),
"a" (type));
#else
asm volatile("ljmpl *%0" : :
"m" (real_mode_header->machine_real_restart_asm),
"D" (type));
#endif
The code switches to the trampoline_pgd, which unmaps the direct mapping
and also the kernel stack. The call to cr4_clear_bits() will find no
stack and crash the machine. The real_mode_header pointer below points
into the direct mapping, and dereferencing it also causes a crash.
The reason this does not crash always is only that kernel mappings are
global and the CR3 switch does not flush those mappings. But if theses
mappings are not in the TLB already, the above code will crash before it
can jump to the real-mode stub.
Extend the trampoline_pgd to contain all kernel mappings to prevent
these crashes and to make code which runs on this page-table more
robust.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20211202153226.22946-5-joro@8bytes.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b50db7095fe002fa3e16605546cba66bf1b68a3e upstream.
There are cases that the TSC clocksource is wrongly judged as unstable by
the clocksource watchdog mechanism which tries to validate the TSC against
HPET, PM_TIMER or jiffies. While there is hardly a general reliable way to
check the validity of a watchdog, Thomas Gleixner proposed [1]:
"I'm inclined to lift that requirement when the CPU has:
1) X86_FEATURE_CONSTANT_TSC
2) X86_FEATURE_NONSTOP_TSC
3) X86_FEATURE_NONSTOP_TSC_S3
4) X86_FEATURE_TSC_ADJUST
5) At max. 4 sockets
After two decades of horrors we're finally at a point where TSC seems
to be halfway reliable and less abused by BIOS tinkerers. TSC_ADJUST
was really key as we can now detect even small modifications reliably
and the important point is that we can cure them as well (not pretty
but better than all other options)."
As feature #3 X86_FEATURE_NONSTOP_TSC_S3 only exists on several generations
of Atom processorz, and is always coupled with X86_FEATURE_CONSTANT_TSC
and X86_FEATURE_NONSTOP_TSC, skip checking it, and also be more defensive
to use maximal 2 sockets.
The check is done inside tsc_init() before registering 'tsc-early' and
'tsc' clocksources, as there were cases that both of them had been
wrongly judged as unreliable.
For more background of tsc/watchdog, there is a good summary in [2]
[tglx} Update vs. jiffies:
On systems where the only remaining clocksource aside of TSC is jiffies
there is no way to make this work because that creates a circular
dependency. Jiffies accuracy depends on not missing a periodic timer
interrupt, which is not guaranteed. That could be detected by TSC, but as
TSC is not trusted this cannot be compensated. The consequence is a
circulus vitiosus which results in shutting down TSC and falling back to
the jiffies clocksource which is even more unreliable.
[1]. https://lore.kernel.org/lkml/87eekfk8bd.fsf@nanos.tec.linutronix.de/
[2]. https://lore.kernel.org/lkml/87a6pimt1f.ffs@nanos.tec.linutronix.de/
[ tglx: Refine comment and amend changelog ]
Fixes: 6e3cd95234dc ("x86/hpet: Use another crystalball to evaluate HPET usability")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211117023751.24190-2-feng.tang@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c7719e79347803b8e3b6b50da8c6db410a3012b5 upstream.
The TSC_ADJUST register is checked every time a CPU enters idle state, but
Thomas Gleixner mentioned there is still a caveat that a system won't enter
idle [1], either because it's too busy or configured purposely to not enter
idle.
Setup a periodic timer (every 10 minutes) to make sure the check is
happening on a regular base.
[1] https://lore.kernel.org/lkml/875z286xtk.fsf@nanos.tec.linutronix.de/
Fixes: 6e3cd95234dc ("x86/hpet: Use another crystalball to evaluate HPET usability")
Requested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211117023751.24190-1-feng.tang@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cb1d220da0faa5ca0deb93449aff953f0c2cce6d ]
If we run the following perf command in an AMD Milan guest:
perf stat \
-e cpu/event=0x1d0/ \
-e cpu/event=0x1c7/ \
-e cpu/umask=0x1f,event=0x18e/ \
-e cpu/umask=0x7,event=0x18e/ \
-e cpu/umask=0x18,event=0x18e/ \
./workload
dmesg will report a #GP warning from an unchecked MSR access
error on MSR_F15H_PERF_CTLx.
This is because according to APM (Revision: 4.03) Figure 13-7,
the bits [35:32] of AMD PerfEvtSeln register is a part of the
event select encoding, which extends the EVENT_SELECT field
from 8 bits to 12 bits.
Opportunistically update pmu->reserved_bits for reserved bit 19.
Reported-by: Jim Mattson <jmattson@google.com>
Fixes: ca724305a2b0 ("KVM: x86/vPMU: Implement AMD vPMU code for KVM")
Signed-off-by: Like Xu <likexu@tencent.com>
Message-Id: <20211118130320.95997-1-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3866ae319c846a612109c008f43cba80b8c15e86 ]
According to the latest uncore document, COMP_BUF_OCCUPANCY (0xd5) event
can be collected on 2-3 counters. Update uncore IIO event constraints for
Skylake Server.
Fixes: cd34cd97b7b4 ("perf/x86/intel/uncore: Add Skylake server uncore support")
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20211115090334.3789-3-alexander.antonov@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e324234e0aa881b7841c7c713306403e12b069ff ]
According Uncore Reference Manual: any of the CHA events may be filtered
by Thread/Core-ID by using tid modifier in CHA Filter 0 Register.
Update skx_cha_hw_config() to follow Uncore Guide.
Fixes: cd34cd97b7b4 ("perf/x86/intel/uncore: Add Skylake server uncore support")
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20211115090334.3789-2-alexander.antonov@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 285f68afa8b20f752b0b7194d54980b5e0e27b75 ]
The following issue is observed with CONFIG_DEBUG_PREEMPT when KVM loads:
KVM: vmx: using Hyper-V Enlightened VMCS
BUG: using smp_processor_id() in preemptible [00000000] code: systemd-udevd/488
caller is set_hv_tscchange_cb+0x16/0x80
CPU: 1 PID: 488 Comm: systemd-udevd Not tainted 5.15.0-rc5+ #396
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.0 12/17/2019
Call Trace:
dump_stack_lvl+0x6a/0x9a
check_preemption_disabled+0xde/0xe0
? kvm_gen_update_masterclock+0xd0/0xd0 [kvm]
set_hv_tscchange_cb+0x16/0x80
kvm_arch_init+0x23f/0x290 [kvm]
kvm_init+0x30/0x310 [kvm]
vmx_init+0xaf/0x134 [kvm_intel]
...
set_hv_tscchange_cb() can get preempted in between acquiring
smp_processor_id() and writing to HV_X64_MSR_REENLIGHTENMENT_CONTROL. This
is not an issue by itself: HV_X64_MSR_REENLIGHTENMENT_CONTROL is a
partition-wide MSR and it doesn't matter which particular CPU will be
used to receive reenlightenment notifications. The only real problem can
(in theory) be observed if the CPU whose id was acquired with
smp_processor_id() goes offline before we manage to write to the MSR,
the logic in hv_cpu_die() won't be able to reassign it correctly.
Reported-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20211012155005.1613352-1-vkuznets@redhat.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7fae4c24a2b84a66c7be399727aca11e7a888462 ]
It turns out that a single page of stack is trivial to overflow with
all the tracing gunk enabled. Raise the exception stacks to 2 pages,
which is still half the interrupt stacks, which are at 4 pages.
Reported-by: Michael Wang <yun.wang@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YUIO9Ye98S5Eb68w@hirez.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 7dfbc624eb5726367900c8d86deff50836240361 upstream.
Check the current VMCS controls to determine if an MSR write will be
intercepted due to MSR bitmaps being disabled. In the nested VMX case,
KVM will disable MSR bitmaps in vmcs02 if they're disabled in vmcs12 or
if KVM can't map L1's bitmaps for whatever reason.
Note, the bad behavior is relatively benign in the current code base as
KVM sets all bits in vmcs02's MSR bitmap by default, clears bits if and
only if L0 KVM also disables interception of an MSR, and only uses the
buggy helper for MSR_IA32_SPEC_CTRL. Because KVM explicitly tests WRMSR
before disabling interception of MSR_IA32_SPEC_CTRL, the flawed check
will only result in KVM reading MSR_IA32_SPEC_CTRL from hardware when it
isn't strictly necessary.
Tag the fix for stable in case a future fix wants to use
msr_write_intercepted(), in which case a buggy implementation in older
kernels could prove subtly problematic.
Fixes: d28b387fb74d ("KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211109013047.2041518-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6ff53f6a438f72998f56e82e76694a1df9d1ea2c upstream.
Add a synchronize_rcu() after clearing the posted interrupt wakeup handler
to ensure all readers, i.e. in-flight IRQ handlers, see the new handler
before returning to the caller. If the caller is an exiting module and
is unregistering its handler, failure to wait could result in the IRQ
handler jumping into an unloaded module.
The registration path doesn't require synchronization, as it's the
caller's responsibility to not generate interrupts it cares about until
after its handler is registered.
Fixes: f6b3c72c2366 ("x86/irq: Define a global vector for VT-d Posted-Interrupts")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211009001107.3936588-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 415de44076640483648d6c0f6d645a9ee61328ad upstream.
Currently, Linux probes for X86_BUG_NULL_SEL unconditionally which
makes it unsafe to migrate in a virtualised environment as the
properties across the migration pool might differ.
To be specific, the case which goes wrong is:
1. Zen1 (or earlier) and Zen2 (or later) in a migration pool
2. Linux boots on Zen2, probes and finds the absence of X86_BUG_NULL_SEL
3. Linux is then migrated to Zen1
Linux is now running on a X86_BUG_NULL_SEL-impacted CPU while believing
that the bug is fixed.
The only way to address the problem is to fully trust the "no longer
affected" CPUID bit when virtualised, because in the above case it would
be clear deliberately to indicate the fact "you might migrate to
somewhere which has this behaviour".
Zen3 adds the NullSelectorClearsBase CPUID bit to indicate that loading
a NULL segment selector zeroes the base and limit fields, as well as
just attributes. Zen2 also has this behaviour but doesn't have the NSCB
bit.
[ bp: Minor touchups. ]
Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20211021104744.24126-1-jane.malalane@citrix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e7d445ab26db833d6640d4c9a08bee176777cc82 upstream.
When runtime support for converting between 4-level and 5-level pagetables
was added to the kernel, the SME code that built pagetables was updated
to use the pagetable functions, e.g. p4d_offset(), etc., in order to
simplify the code. However, the use of the pagetable functions in early
boot code requires the use of the USE_EARLY_PGTABLE_L5 #define in order to
ensure that the proper definition of pgtable_l5_enabled() is used.
Without the #define, pgtable_l5_enabled() is #defined as
cpu_feature_enabled(X86_FEATURE_LA57). In early boot, the CPU features
have not yet been discovered and populated, so pgtable_l5_enabled() will
return false even when 5-level paging is enabled. This causes the SME code
to always build 4-level pagetables to perform the in-place encryption.
If 5-level paging is enabled, switching to the SME pagetables results in
a page-fault that kills the boot.
Adding the #define results in pgtable_l5_enabled() using the
__pgtable_l5_enabled variable set in early boot and the SME code building
pagetables for the proper paging level.
Fixes: aad983913d77 ("x86/mm/encrypt: Simplify sme_populate_pgd() and sme_populate_pgd_large()")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org> # 4.18.x
Link: https://lkml.kernel.org/r/2cb8329655f5c753905812d951e212022a480475.1634318656.git.thomas.lendacky@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1e254d0d86a0f2efd4190a89d5204b37c18c6381 upstream.
This reverts commit 76b4f357d0e7d8f6f0013c733e6cba1773c266d3.
The commit has the wrong reasoning, as KVM_MAX_VCPU_ID is not defining the
maximum allowed vcpu-id as its name suggests, but the number of vcpu-ids.
So revert this patch again.
Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210913135745.13944-2-jgross@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 711885906b5c2df90746a51f4cd674f1ab9fbb1d upstream.
This Kconfig option was added initially so that memory encryption is
enabled by default on machines which support it.
However, devices which have DMA masks that are less than the bit
position of the encryption bit, aka C-bit, require the use of an IOMMU
or the use of SWIOTLB.
If the IOMMU is disabled or in passthrough mode, the kernel would switch
to SWIOTLB bounce-buffering for those transfers.
In order to avoid that,
2cc13bb4f59f ("iommu: Disable passthrough mode when SME is active")
disables the default IOMMU passthrough mode so that devices for which the
default 256K DMA is insufficient, can use the IOMMU instead.
However 2, there are cases where the IOMMU is disabled in the BIOS, etc.
(think the usual hardware folk "oops, I dropped the ball there" cases) or a
driver doesn't properly use the DMA APIs or a device has a firmware or
hardware bug, e.g.:
ea68573d408f ("drm/amdgpu: Fail to load on RAVEN if SME is active")
However 3, in the above GPU use case, there are APIs like Vulkan and
some OpenGL/OpenCL extensions which are under the assumption that
user-allocated memory can be passed in to the kernel driver and both the
GPU and CPU can do coherent and concurrent access to the same memory.
That cannot work with SWIOTLB bounce buffers, of course.
So, in order for those devices to function, drop the "default y" for the
SME by default active option so that users who want to have SME enabled,
will need to either enable it in their config or use "mem_encrypt=on" on
the kernel command line.
[ tlendacky: Generalize commit message. ]
Fixes: 7744ccdbc16f ("x86/mm: Add Secure Memory Encryption (SME) support")
Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/8bbacd0e-4580-3194-19d2-a0ecad7df09c@molgen.mpg.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64e87d4bd3201bf8a4685083ee4daf5c0d001452 upstream.
domain_add_cpu() is called whenever a CPU is brought online. The
earlier call to domain_setup_ctrlval() allocates the control value
arrays.
If domain_setup_mon_state() fails, the control value arrays are not
freed.
Add the missing kfree() calls.
Fixes: 1bd2a63b4f0de ("x86/intel_rdt/mba_sc: Add initialization support")
Fixes: edf6fa1c4a951 ("x86/intel_rdt/cqm: Add RMID (Resource monitoring ID) management")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20210917165958.28313-1-james.morse@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 225bac2dc5d192e55f2c50123ee539b1edf8a411 upstream.
Commit in Fixes intended to exclude the Winchip series and referred to
CONFIG_WINCHIP3D, but the config symbol is called CONFIG_MWINCHIP3D.
Hence, scripts/checkkconfigsymbols.py warns:
WINCHIP3D
Referencing files: arch/x86/Kconfig
Correct the reference to the intended config symbol.
Fixes: 69b8d3fcabdc ("x86/Kconfig: Exclude i586-class CPUs lacking PAE support from the HIGHMEM64G Kconfig group")
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20210803113531.30720-4-lukas.bulwahn@gmail.com
[manually adjusted the change to the state on the v4.19.y and v5.4.y stable tree]
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6e3cd95234dc1eda488f4f487c281bac8fef4d9b upstream.
On recent Intel systems the HPET stops working when the system reaches PC10
idle state.
The approach of adding PCI ids to the early quirks to disable HPET on
these systems is a whack a mole game which makes no sense.
Check for PC10 instead and force disable HPET if supported. The check is
overbroad as it does not take ACPI, intel_idle enablement and command
line parameters into account. That's fine as long as there is at least
PMTIMER available to calibrate the TSC frequency. The decision can be
overruled by adding "hpet=force" on the kernel command line.
Remove the related early PCI quirks for affected Ice Cake and Coffin Lake
systems as they are not longer required. That should also cover all
other systems, i.e. Tiger Rag and newer generations, which are most
likely affected by this as well.
Fixes: Yet another hardware trainwreck
Reported-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael@kernel.org>
Cc: stable@vger.kernel.org
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4758fd801f919b8b9acad78d2e49a195ec2be46b upstream.
The refactoring in the commit in Fixes introduced an ifdef
CONFIG_OLPC_XO1_5_SCI, however the config symbol is actually called
"CONFIG_OLPC_XO15_SCI".
Fortunately, ./scripts/checkkconfigsymbols.py warns:
OLPC_XO1_5_SCI
Referencing files: arch/x86/platform/olpc/olpc.c
Correct this ifdef condition to the intended config symbol.
Fixes: ec9964b48033 ("Platform: OLPC: Move EC-specific functionality out from x86")
Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20210803113531.30720-3-lukas.bulwahn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 02d029a41dc986e2d5a77ecca45803857b346829 upstream.
perf_init_event tries multiple init callbacks and does not reset the
event state between tries. When x86_pmu_event_init runs, it
unconditionally sets the destroy callback to hw_perf_event_destroy. On
the next init attempt after x86_pmu_event_init, in perf_try_init_event,
if the pmu's capabilities includes PERF_PMU_CAP_NO_EXCLUDE, the destroy
callback will be run. However, if the next init didn't set the destroy
callback, hw_perf_event_destroy will be run (since the callback wasn't
reset).
Looking at other pmu init functions, the common pattern is to only set
the destroy callback on a successful init. Resetting the callback on
failure tries to replicate that pattern.
This was discovered after commit f11dd0d80555 ("perf/x86/amd/ibs: Extend
PERF_PMU_CAP_NO_EXCLUDE to IBS Op") when the second (and only second)
run of the perf tool after a reboot results in 0 samples being
generated. The extra run of hw_perf_event_destroy results in
active_events having an extra decrement on each perf run. The second run
has active_events == 0 and every subsequent run has active_events < 0.
When active_events == 0, the NMI handler will early-out and not record
any samples.
Signed-off-by: Anand K Mistry <amistry@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210929170405.1.I078b98ee7727f9ae9d6df8262bad7e325e40faf0@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e1fc1553cd78292ab3521c94c9dd6e3e70e606a1 ]
Intel PMU MSRs is in msrs_to_save_all[], so add AMD PMU MSRs to have a
consistent behavior between Intel and AMD when using KVM_GET_MSRS,
KVM_SET_MSRS or KVM_GET_MSR_INDEX_LIST.
We have to add legacy and new MSRs to handle guests running without
X86_FEATURE_PERFCTR_CORE.
Signed-off-by: Fares Mehanna <faresx@amazon.de>
Message-Id: <20210915133951.22389-1-faresx@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ecc2123e09f9e71ddc6c53d71e283b8ada685fe2 ]
According to the latest event list, the event encoding 0xEF is only
available on the first 4 counters. Add it into the event constraints
table.
Fixes: 6017608936c1 ("perf/x86/intel: Add Icelake support")
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/1632842343-25862-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ad9af930680bb396c87582edc172b3a7cf2a3fbf upstream.
There're other modules might use hv_clock_per_cpu variable like ptp_kvm,
so move it into kvmclock.h and export the symbol to make it visiable to
other modules.
Signed-off-by: Zelin Deng <zelin.deng@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Message-Id: <1632892429-101194-2-git-send-email-zelin.deng@linux.alibaba.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 0594c58161b6e0f3da8efa9c6e3d4ba52b652717 upstream.
The initial observation was that in PV mode under Xen 32-bit user space
didn't work anymore. Attempts of system calls ended in #GP(0x402). All
of the sudden the vector 0x80 handler was not in place anymore. As it
turns out up to 5.13 redundant initialization did occur: Once from
cpu_initialize_context() (through its VCPUOP_initialise hypercall) and a
2nd time while each CPU was brought fully up. This 2nd initialization is
now gone, uncovering that the 1st one was flawed: Unlike for the
set_trap_table hypercall, a full virtual IDT needs to be specified here;
the "vector" fields of the individual entries are of no interest. With
many (kernel) IDT entries still(?) (i.e. at that point at least) empty,
the syscall vector 0x80 ended up in slot 0x20 of the virtual IDT, thus
becoming the domain's handler for vector 0x20.
Make xen_convert_trap_info() fit for either purpose, leveraging the fact
that on the xen_copy_trap_info() path the table starts out zero-filled.
This includes moving out the writing of the sentinel, which would also
have lead to a buffer overrun in the xen_copy_trap_info() case if all
(kernel) IDT entries were populated. Convert the writing of the sentinel
to clearing of the entire table entry rather than just the address
field.
(I didn't bother trying to identify the commit which uncovered the issue
in 5.14; the commit named below is the one which actually introduced the
bad code.)
Fixes: f87e4cac4f4e ("xen: SMP guest support")
Cc: stable@vger.kernel.org
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/7a266932-092e-b68f-f2bb-1473b61adc6e@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 4b92d4add5f6dcf21275185c997d6ecb800054cd ]
DEFINE_SMP_CALL_CACHE_FUNCTION() was usefel before the CPU hotplug rework
to ensure that the cache related functions are called on the upcoming CPU
because the notifier itself could run on any online CPU.
The hotplug state machine guarantees that the callbacks are invoked on the
upcoming CPU. So there is no need to have this SMP function call
obfuscation. That indirection was missed when the hotplug notifiers were
converted.
This also solves the problem of ARM64 init_cache_level() invoking ACPI
functions which take a semaphore in that context. That's invalid as SMP
function calls run with interrupts disabled. Running it just from the
callback in context of the CPU hotplug thread solves this.
Fixes: 8571890e1513 ("arm64: Add support for ACPI based firmware tables")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/871r69ersb.ffs@tglx
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 34b1999da935a33be6239226bfa6cd4f704c5c88 upstream.
Jiri Olsa reported a fault when running:
# cat /proc/kallsyms | grep ksys_read
ffffffff8136d580 T ksys_read
# objdump -d --start-address=0xffffffff8136d580 --stop-address=0xffffffff8136d590 /proc/kcore
/proc/kcore: file format elf64-x86-64
Segmentation fault
general protection fault, probably for non-canonical address 0xf887ffcbff000: 0000 [#1] SMP PTI
CPU: 12 PID: 1079 Comm: objdump Not tainted 5.14.0-rc5qemu+ #508
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-4.fc34 04/01/2014
RIP: 0010:kern_addr_valid
Call Trace:
read_kcore
? rcu_read_lock_sched_held
? rcu_read_lock_sched_held
? rcu_read_lock_sched_held
? trace_hardirqs_on
? rcu_read_lock_sched_held
? lock_acquire
? lock_acquire
? rcu_read_lock_sched_held
? lock_acquire
? rcu_read_lock_sched_held
? rcu_read_lock_sched_held
? rcu_read_lock_sched_held
? lock_release
? _raw_spin_unlock
? __handle_mm_fault
? rcu_read_lock_sched_held
? lock_acquire
? rcu_read_lock_sched_held
? lock_release
proc_reg_read
? vfs_read
vfs_read
ksys_read
do_syscall_64
entry_SYSCALL_64_after_hwframe
The fault happens because kern_addr_valid() dereferences existent but not
present PMD in the high kernel mappings.
Such PMDs are created when free_kernel_image_pages() frees regions larger
than 2Mb. In this case, a part of the freed memory is mapped with PMDs and
the set_memory_np_noalias() -> ... -> __change_page_attr() sequence will
mark the PMD as not present rather than wipe it completely.
Have kern_addr_valid() check whether higher level page table entries are
present before trying to dereference them to fix this issue and to avoid
similar issues in the future.
Stable backporting note:
------------------------
Note that the stable marking is for all active stable branches because
there could be cases where pagetable entries exist but are not valid -
see 9a14aefc1d28 ("x86: cpa, fix lookup_address"), for example. So make
sure to be on the safe side here and use pXY_present() accessors rather
than pXY_none() which could #GP when accessing pages in the direct map.
Also see:
c40a56a7818c ("x86/mm/init: Remove freed kernel image areas from alias mapping")
for more info.
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: <stable@vger.kernel.org> # 4.4+
Link: https://lkml.kernel.org/r/20210819132717.19358-1-rppt@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4b511d5bfa74b1926daefd1694205c7f1bcf677f upstream.
Xen PV guests are specifying the highest used PFN via the max_pfn
field in shared_info. This value is used by the Xen tools when saving
or migrating the guest.
Unfortunately this field is misnamed, as in reality it is specifying
the number of pages (including any memory holes) of the guest, so it
is the highest used PFN + 1. Renaming isn't possible, as this is a
public Xen hypervisor interface which needs to be kept stable.
The kernel will set the value correctly initially at boot time, but
when adding more pages (e.g. due to memory hotplug or ballooning) a
real PFN number is stored in max_pfn. This is done when expanding the
p2m array, and the PFN stored there is even possibly wrong, as it
should be the last possible PFN of the just added P2M frame, and not
one which led to the P2M expansion.
Fix that by setting shared_info->max_pfn to the last possible PFN + 1.
Fixes: 98dd166ea3a3c3 ("x86/xen/p2m: hint at the last populated P2M entry")
Cc: stable@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Link: https://lore.kernel.org/r/20210730092622.9973-2-jgross@suse.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f7782bb8d818d8f47c26b22079db10599922787a upstream.
Clear nested.pi_pending on nested VM-Enter even if L2 will run without
posted interrupts enabled. If nested.pi_pending is left set from a
previous L2, vmx_complete_nested_posted_interrupt() will pick up the
stale flag and exit to userspace with an "internal emulation error" due
the new L2 not having a valid nested.pi_desc.
Arguably, vmx_complete_nested_posted_interrupt() should first check for
posted interrupts being enabled, but it's also completely reasonable that
KVM wouldn't screw up a fundamental flag. Not to mention that the mere
existence of nested.pi_pending is a long-standing bug as KVM shouldn't
move the posted interrupt out of the IRR until it's actually processed,
e.g. KVM effectively drops an interrupt when it performs a nested VM-Exit
with a "pending" posted interrupt. Fixing the mess is a future problem.
Prior to vmx_complete_nested_posted_interrupt() interpreting a null PI
descriptor as an error, this was a benign bug as the null PI descriptor
effectively served as a check on PI not being enabled. Even then, the
new flow did not become problematic until KVM started checking the result
of kvm_check_nested_events().
Fixes: 705699a13994 ("KVM: nVMX: Enable nested posted interrupt processing")
Fixes: 966eefb89657 ("KVM: nVMX: Disable vmcs02 posted interrupts if vmcs12 PID isn't mappable")
Fixes: 47d3530f86c0 ("KVM: x86: Exit to userspace when kvm_check_nested_events fails")
Cc: stable@vger.kernel.org
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210810144526.2662272-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d9130a2dfdd4b21736c91b818f87dbc0ccd1e757 upstream.
When MSR_IA32_TSC_ADJUST is written by guest due to TSC ADJUST feature
especially there's a big tsc warp (like a new vCPU is hot-added into VM
which has been up for a long time), tsc_offset is added by a large value
then go back to guest. This causes system time jump as tsc_timestamp is
not adjusted in the meantime and pvclock monotonic character.
To fix this, just notify kvm to update vCPU's guest time before back to
guest.
Cc: stable@vger.kernel.org
Signed-off-by: Zelin Deng <zelin.deng@linux.alibaba.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1619576521-81399-2-git-send-email-zelin.deng@linux.alibaba.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 527f721478bce3f49b513a733bacd19d6f34b08c upstream.
The recent commit
064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")
caused a RHEL build failure with an uninitialized variable warning
treated as an error because it removed the default case snippet.
The RHEL Makefile uses '-Werror=maybe-uninitialized' to force possibly
uninitialized variable warnings to be treated as errors. This is also
reported by smatch via the 0day robot.
The error from the RHEL build is:
arch/x86/kernel/cpu/resctrl/monitor.c: In function ‘__mon_event_count’:
arch/x86/kernel/cpu/resctrl/monitor.c:261:12: error: ‘m’ may be used
uninitialized in this function [-Werror=maybe-uninitialized]
m->chunks += chunks;
^~
The upstream Makefile does not build using '-Werror=maybe-uninitialized'.
So, the problem is not seen there. Fix the problem by putting back the
default case snippet.
[ bp: note that there's nothing wrong with the code and other compilers
do not trigger this warning - this is being done just so the RHEL compiler
is happy. ]
Fixes: 064855a69003 ("x86/resctrl: Fix default monitoring groups reporting")
Reported-by: Terry Bowman <Terry.Bowman@amd.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/162949631908.23903.17090272726012848523.stgit@bmoger-ubuntu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f5e81d1117501546b7be050c5fbafa6efd2c722c upstream.
In case of JITs, each of the JIT backends compiles the BPF nospec instruction
/either/ to a machine instruction which emits a speculation barrier /or/ to
/no/ machine instruction in case the underlying architecture is not affected
by Speculative Store Bypass or has different mitigations in place already.
This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence'
instruction for mitigation. In case of arm64, we rely on the firmware mitigation
as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled,
it works for all of the kernel code with no need to provide any additional
instructions here (hence only comment in arm64 JIT). Other archs can follow
as needed. The BPF nospec instruction is specifically targeting Spectre v4
since i) we don't use a serialization barrier for the Spectre v1 case, and
ii) mitigation instructions for v1 and v4 might be different on some archs.
The BPF nospec is required for a future commit, where the BPF verifier does
annotate intermediate BPF programs with speculation barriers.
Co-developed-by: Piotr Krysiuk <piotras@gmail.com>
Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[OP: - adjusted context for 5.4
- apply riscv changes to /arch/riscv/net/bpf_jit_comp.c]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a729691b541f6e63043beae72e635635abe5dc09 upstream.
When this platform was relatively new in November 2011, with early BIOS
revisions, a reboot quirk was added in commit 6be30bb7d750 ("x86/reboot:
Blacklist Dell OptiPlex 990 known to require PCI reboot")
However, this quirk (and several others) are open-ended to all BIOS
versions and left no automatic expiry if/when the system BIOS fixed the
issue, meaning that nobody is likely to come along and re-test.
What is really problematic with using PCI reboot as this quirk does, is
that it causes this platform to do a full power down, wait one second,
and then power back on. This is less than ideal if one is using it for
boot testing and/or bisecting kernels when legacy rotating hard disks
are installed.
It was only by chance that the quirk was noticed in dmesg - and when
disabled it turned out that it wasn't required anymore (BIOS A24), and a
default reboot would work fine without the "harshness" of power cycling the
machine (and disks) down and up like the PCI reboot does.
Doing a bit more research, it seems that the "newest" BIOS for which the
issue was reported[1] was version A06, however Dell[2] seemed to suggest
only up to and including version A05, with the A06 having a large number of
fixes[3] listed.
As is typical with a new platform, the initial BIOS updates come frequently
and then taper off (and in this case, with a revival for CPU CVEs); a
search for O990-A<ver>.exe reveals the following dates:
A02 16 Mar 2011
A03 11 May 2011
A06 14 Sep 2011
A07 24 Oct 2011
A10 08 Dec 2011
A14 06 Sep 2012
A16 15 Oct 2012
A18 30 Sep 2013
A19 23 Sep 2015
A20 02 Jun 2017
A23 07 Mar 2018
A24 21 Aug 2018
While it's overkill to flash and test each of the above, it would seem
likely that the issue was contained within A0x BIOS versions, given the
dates above and the dates of issue reports[4] from distros. So rather than
just throw out the quirk entirely, limit the scope to just those early BIOS
versions, in case people are still running systems from 2011 with the
original as-shipped early A0x BIOS versions.
[1] https://lore.kernel.org/lkml/1320373471-3942-1-git-send-email-trenn@suse.de/
[2] https://www.dell.com/support/kbdoc/en-ca/000131908/linux-based-operating-systems-stall-upon-reboot-on-optiplex-390-790-990-systems
[3] https://www.dell.com/support/home/en-ca/drivers/driversdetails?driverid=85j10
[4] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/768039
Fixes: 6be30bb7d750 ("x86/reboot: Blacklist Dell OptiPlex 990 known to require PCI reboot")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210530162447.996461-4-paul.gortmaker@windriver.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e10de314287c2c14b0e6f0e3e961975ce2f4a83d upstream.
On certain AMD platforms, when the IOMMU performance counter source
(csource) field is zero, power-gating for the counter is enabled, which
prevents write access and returns zero for read access.
This can cause invalid perf result especially when event multiplexing
is needed (i.e. more number of events than available counters) since
the current logic keeps track of the previously read counter value,
and subsequently re-program the counter to continue counting the event.
With power-gating enabled, we cannot gurantee successful re-programming
of the counter.
Workaround this issue by :
1. Modifying the ordering of setting/reading counters and enabing/
disabling csources to only access the counter when the csource
is set to non-zero.
2. Since AMD IOMMU PMU does not support interrupt mode, the logic
can be simplified to always start counting with value zero,
and accumulate the counter value when stopping without the need
to keep track and reprogram the counter with the previously read
counter value.
This has been tested on systems with and without power-gating.
Fixes: 994d6608efe4 ("iommu/amd: Remove performance counter pre-initialization test")
Suggested-by: Alexander Monakov <amonakov@ispras.ru>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210504065236.4415-1-suravee.suthikulpanit@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 26db2e0c51fe83e1dd852c1321407835b481806e ]
Erratum #1197 "IBS (Instruction Based Sampling) Register State May be
Incorrect After Restore From CC6" is published in a document:
"Revision Guide for AMD Family 19h Models 00h-0Fh Processors" 56683 Rev. 1.04 July 2021
https://bugzilla.kernel.org/show_bug.cgi?id=206537
Implement the erratum's suggested workaround and ignore IBS samples if
MSRC001_1031 == 0.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210817221048.88063-3-kim.phillips@amd.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c53c6b7409f4cd9e542991b53d597fbe2751d7db ]
Per SDM, bit 2:0 of CPUID(0x14,1).EAX[2:0] reports the number of
configurable address ranges for filtering, not bit 1:0.
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20210824040622.4081502-1-xiaoyao.li@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
