Pull x86 fixes from Borislav Petkov:
- Make sure the poking PGD is pinned for Xen PV as it requires it this
way
- Fixes for two resctrl races when moving a task or creating a new
monitoring group
- Fix SEV-SNP guests running under HyperV where MTRRs are disabled to
not return a UC- type mapping type on memremap() and thus cause a
serious slowdown
- Fix insn mnemonics in bioscall.S now that binutils is starting to fix
confusing insn suffixes
* tag 'x86_urgent_for_v6.2_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: fix poking_init() for Xen PV guests
x86/resctrl: Fix event counts regression in reused RMIDs
x86/resctrl: Fix task CLOSID/RMID update race
x86/pat: Fix pat_x_mtrr_type() for MTRR disabled case
x86/boot: Avoid using Intel mnemonics in AT&T syntax asm
Pull powerpc fixes from Michael Ellerman:
- Fix a build failure with some versions of ld that have an odd version
string
- Fix incorrect use of mutex in the IMC PMU driver
Thanks to Kajol Jain, Michael Petlan, Ojaswin Mujoo, Peter Zijlstra, and
Yang Yingliang.
* tag 'powerpc-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s/hash: Make stress_hpt_timer_fn() static
powerpc/imc-pmu: Fix use of mutex in IRQs disabled section
powerpc/boot: Fix incorrect version calculation issue in ld_version
Pull pci fixes from Bjorn Helgaas:
- Work around apparent firmware issue that made Linux reject MMCONFIG
space, which broke PCI extended config space (Bjorn Helgaas)
- Fix CONFIG_PCIE_BT1 dependency due to mid-air collision between a
PCI_MSI_IRQ_DOMAIN -> PCI_MSI change and addition of PCIE_BT1 (Lukas
Bulwahn)
* tag 'pci-v6.2-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
x86/pci: Treat EfiMemoryMappedIO as reservation of ECAM space
x86/pci: Simplify is_mmconf_reserved() messages
PCI: dwc: Adjust to recent removal of PCI_MSI_IRQ_DOMAIN
Pull kvm fixes from Paolo Bonzini:
"ARM:
- Fix the PMCR_EL0 reset value after the PMU rework
- Correctly handle S2 fault triggered by a S1 page table walk by not
always classifying it as a write, as this breaks on R/O memslots
- Document why we cannot exit with KVM_EXIT_MMIO when taking a write
fault from a S1 PTW on a R/O memslot
- Put the Apple M2 on the naughty list for not being able to
correctly implement the vgic SEIS feature, just like the M1 before
it
- Reviewer updates: Alex is stepping down, replaced by Zenghui
x86:
- Fix various rare locking issues in Xen emulation and teach lockdep
to detect them
- Documentation improvements
- Do not return host topology information from KVM_GET_SUPPORTED_CPUID"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86/xen: Avoid deadlock by adding kvm->arch.xen.xen_lock leaf node lock
KVM: Ensure lockdep knows about kvm->lock vs. vcpu->mutex ordering rule
KVM: x86/xen: Fix potential deadlock in kvm_xen_update_runstate_guest()
KVM: x86/xen: Fix lockdep warning on "recursive" gpc locking
Documentation: kvm: fix SRCU locking order docs
KVM: x86: Do not return host topology information from KVM_GET_SUPPORTED_CPUID
KVM: nSVM: clarify recalc_intercepts() wrt CR8
MAINTAINERS: Remove myself as a KVM/arm64 reviewer
MAINTAINERS: Add Zenghui Yu as a KVM/arm64 reviewer
KVM: arm64: vgic: Add Apple M2 cpus to the list of broken SEIS implementations
KVM: arm64: Convert FSC_* over to ESR_ELx_FSC_*
KVM: arm64: Document the behaviour of S1PTW faults on RO memslots
KVM: arm64: Fix S1PTW handling on RO memslots
KVM: arm64: PMU: Fix PMCR_EL0 reset value
Pull EFI fixes from Ard Biesheuvel:
- avoid a potential crash on the efi_subsys_init() error path
- use more appropriate error code for runtime services calls issued
after a crash in the firmware occurred
- avoid READ_ONCE() for accessing firmware tables that may appear
misaligned in memory
* tag 'efi-fixes-for-v6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
efi: tpm: Avoid READ_ONCE() for accessing the event log
efi: rt-wrapper: Add missing include
efi: fix userspace infinite retry read efivars after EFI runtime services page fault
efi: fix NULL-deref in init error path
Pull arm64 fixes from Will Deacon:
"Here's a sizeable batch of Friday the 13th arm64 fixes for -rc4. What
could possibly go wrong?
The obvious reason we have so much here is because of the holiday
season right after the merge window, but we've also brought back an
erratum workaround that was previously dropped at the last minute and
there's an MTE coredumping fix that strays outside of the arch/arm64
directory.
Summary:
- Fix PAGE_TABLE_CHECK failures on hugepage splitting path
- Fix PSCI encoding of MEM_PROTECT_RANGE function in UAPI header
- Fix NULL deref when accessing debugfs node if PSCI is not present
- Fix MTE core dumping when VMA list is being updated concurrently
- Fix SME signal frame handling when SVE is not implemented by the
CPU
- Fix asm constraints for cmpxchg_double() to hazard both words
- Fix build failure with stack tracer and older versions of Clang
- Bring back workaround for Cortex-A715 erratum 2645198"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: Fix build with CC=clang, CONFIG_FTRACE=y and CONFIG_STACK_TRACER=y
arm64/mm: Define dummy pud_user_exec() when using 2-level page-table
arm64: errata: Workaround possible Cortex-A715 [ESR|FAR]_ELx corruption
firmware/psci: Don't register with debugfs if PSCI isn't available
firmware/psci: Fix MEM_PROTECT_RANGE function numbers
arm64/signal: Always allocate SVE signal frames on SME only systems
arm64/signal: Always accept SVE signal frames on SME only systems
arm64/sme: Fix context switch for SME only systems
arm64: cmpxchg_double*: hazard against entire exchange variable
arm64/uprobes: change the uprobe_opcode_t typedef to fix the sparse warning
arm64: mte: Avoid the racy walk of the vma list during core dump
elfcore: Add a cprm parameter to elf_core_extra_{phdrs,data_size}
arm64: mte: Fix double-freeing of the temporary tag storage during coredump
arm64: ptrace: Use ARM64_SME to guard the SME register enumerations
arm64/mm: add pud_user_exec() check in pud_user_accessible_page()
arm64/mm: fix incorrect file_map_count for invalid pmd
Pull s390 fixes from Heiko Carstens:
- Add various missing READ_ONCE() to cmpxchg() loops prevent the
compiler from potentially generating incorrect code. This includes a
rather large change to the s390 specific hardware sampling code and
its current use of cmpxchg_double().
Do the fix now to get it out of the way of Peter Zijlstra's
cmpxchg128() work, and have something that can be backported. The
added new code includes a private 128 bit cmpxchg variant which will
be removed again after Peter's rework is available. Also note that
this 128 bit cmpxchg variant is used to implement 128 bit
READ_ONCE(), while strictly speaking it wouldn't be necessary, and
_READ_ONCE() should also be sufficient; even though it isn't obvious
for all converted locations that this is the case. Therefore use this
implementation for for the sake of clarity and consistency for now.
- Fix ipl report address handling to avoid kdump failures/hangs.
- Fix misuse of #(el)if in kernel decompressor.
- Define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36,
caused by the recently changed discard behaviour.
- Make sure _edata and _end symbols are always page aligned.
- The current header guard DEBUG_H in one of the s390 specific header
files is too generic and conflicts with the ath9k wireless driver.
Add an _ASM_S390_ prefix to the guard to make it unique.
- Update defconfigs.
* tag 's390-6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: update defconfigs
KVM: s390: interrupt: use READ_ONCE() before cmpxchg()
s390/percpu: add READ_ONCE() to arch_this_cpu_to_op_simple()
s390/cpum_sf: add READ_ONCE() semantics to compare and swap loops
s390/kexec: fix ipl report address for kdump
s390: fix -Wundef warning for CONFIG_KERNEL_ZSTD
s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36
s390: expicitly align _edata and _end symbols on page boundary
s390/debug: add _ASM_S390_ prefix to header guard
Pull xen fixes from Juergen Gross:
- two cleanup patches
- a fix of a memory leak in the Xen pvfront driver
- a fix of a locking issue in the Xen hypervisor console driver
* tag 'for-linus-6.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pvcalls: free active map buffer on pvcalls_front_free_map
hvc/xen: lock console list traversal
x86/xen: Remove the unused function p2m_index()
xen: make remove callback of xen driver void returned
Pull perf events hw enablement from Ingo Molnar:
- More hardware-enablement for Intel Meteor Lake & Emerald Rapid
systems: pure model ID enumeration additions that do not affect other
systems.
* tag 'perf-urgent-2023-01-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Add Emerald Rapids
perf/x86/msr: Add Emerald Rapids
perf/x86/msr: Add Meteor Lake support
perf/x86/cstate: Add Meteor Lake support
Commit 3f4c8211d9 ("x86/mm: Use mm_alloc() in poking_init()") broke
the kernel for running as Xen PV guest.
It seems as if the new address space is never activated before being
used, resulting in Xen rejecting to accept the new CR3 value (the PGD
isn't pinned).
Fix that by adding the now missing call of paravirt_arch_dup_mmap() to
poking_init(). That call was previously done by dup_mm()->dup_mmap() and
it is a NOP for all cases but for Xen PV, where it is just doing the
pinning of the PGD.
Fixes: 3f4c8211d9 ("x86/mm: Use mm_alloc() in poking_init()")
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230109150922.10578-1-jgross@suse.com
In commit 14243b3871 ("KVM: x86/xen: Add KVM_IRQ_ROUTING_XEN_EVTCHN
and event channel delivery") the clever version of me left some helpful
notes for those who would come after him:
/*
* For the irqfd workqueue, using the main kvm->lock mutex is
* fine since this function is invoked from kvm_set_irq() with
* no other lock held, no srcu. In future if it will be called
* directly from a vCPU thread (e.g. on hypercall for an IPI)
* then it may need to switch to using a leaf-node mutex for
* serializing the shared_info mapping.
*/
mutex_lock(&kvm->lock);
In commit 2fd6df2f2b ("KVM: x86/xen: intercept EVTCHNOP_send from guests")
the other version of me ran straight past that comment without reading it,
and introduced a potential deadlock by taking vcpu->mutex and kvm->lock
in the wrong order.
Solve this as originally suggested, by adding a leaf-node lock in the Xen
state rather than using kvm->lock for it.
Fixes: 2fd6df2f2b ("KVM: x86/xen: intercept EVTCHNOP_send from guests")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20230111180651.14394-4-dwmw2@infradead.org>
[Rebase, add docs. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The kvm_xen_update_runstate_guest() function can be called when the vCPU
is being scheduled out, from a preempt notifier. It *opportunistically*
updates the runstate area in the guest memory, if the gfn_to_pfn_cache
which caches the appropriate address is still valid.
If there is *contention* when it attempts to obtain gpc->lock, then
locking inside the priority inheritance checks may cause a deadlock.
Lockdep reports:
[13890.148997] Chain exists of:
&gpc->lock --> &p->pi_lock --> &rq->__lock
[13890.149002] Possible unsafe locking scenario:
[13890.149003] CPU0 CPU1
[13890.149004] ---- ----
[13890.149005] lock(&rq->__lock);
[13890.149007] lock(&p->pi_lock);
[13890.149009] lock(&rq->__lock);
[13890.149011] lock(&gpc->lock);
[13890.149013]
*** DEADLOCK ***
In the general case, if there's contention for a read lock on gpc->lock,
that's going to be because something else is either invalidating or
revalidating the cache. Either way, we've raced with seeing it in an
invalid state, in which case we would have aborted the opportunistic
update anyway.
So in the 'atomic' case when called from the preempt notifier, just
switch to using read_trylock() and avoid the PI handling altogether.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20230111180651.14394-2-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In commit 5ec3289b31 ("KVM: x86/xen: Compatibility fixes for shared runstate
area") we declared it safe to obtain two gfn_to_pfn_cache locks at the same
time:
/*
* The guest's runstate_info is split across two pages and we
* need to hold and validate both GPCs simultaneously. We can
* declare a lock ordering GPC1 > GPC2 because nothing else
* takes them more than one at a time.
*/
However, we forgot to tell lockdep. Do so, by setting a subclass on the
first lock before taking the second.
Fixes: 5ec3289b31 ("KVM: x86/xen: Compatibility fixes for shared runstate area")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <20230111180651.14394-1-dwmw2@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM/arm64 fixes for 6.2, take #1
- Fix the PMCR_EL0 reset value after the PMU rework
- Correctly handle S2 fault triggered by a S1 page table walk
by not always classifying it as a write, as this breaks on
R/O memslots
- Document why we cannot exit with KVM_EXIT_MMIO when taking
a write fault from a S1 PTW on a R/O memslot
- Put the Apple M2 on the naughty step for not being able to
correctly implement the vgic SEIS feature, just liek the M1
before it
- Reviewer updates: Alex is stepping down, replaced by Zenghui
Make sure that *ptr__ within arch_this_cpu_to_op_simple() is only
dereferenced once by using READ_ONCE(). Otherwise the compiler could
generate incorrect code.
Cc: <stable@vger.kernel.org>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The current cmpxchg_double() loops within the perf hw sampling code do not
have READ_ONCE() semantics to read the old value from memory. This allows
the compiler to generate code which reads the "old" value several times
from memory, which again allows for inconsistencies.
For example:
/* Reset trailer (using compare-double-and-swap) */
do {
te_flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK;
te_flags |= SDB_TE_ALERT_REQ_MASK;
} while (!cmpxchg_double(&te->flags, &te->overflow,
te->flags, te->overflow,
te_flags, 0ULL));
The compiler could generate code where te->flags used within the
cmpxchg_double() call may be refetched from memory and which is not
necessarily identical to the previous read version which was used to
generate te_flags. Which in turn means that an incorrect update could
happen.
Fix this by adding READ_ONCE() semantics to all cmpxchg_double()
loops. Given that READ_ONCE() cannot generate code on s390 which atomically
reads 16 bytes, use a private compare-and-swap-double implementation to
achieve that.
Also replace cmpxchg_double() with the private implementation to be able to
re-use the old value within the loops.
As a side effect this converts the whole code to only use bit fields
to read and modify bits within the hws trailer header.
Reported-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Reviewed-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/linux-s390/Y71QJBhNTIatvxUT@osiris/T/#ma14e2a5f7aa8ed4b94b6f9576799b3ad9c60f333
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.
Command to trigger the warning:
# perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5
Performance counter stats for 'sleep 5':
0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/
5.002117947 seconds time elapsed
0.000131000 seconds user
0.001063000 seconds sys
Below is snippet of the warning in dmesg:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
preempt_count: 2, expected: 0
4 locks held by perf-exec/2869:
#0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
#1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
#2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
#3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
irq event stamp: 4806
hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0
hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510
softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
Call Trace:
dump_stack_lvl+0x98/0xe0 (unreliable)
__might_resched+0x2f8/0x310
__mutex_lock+0x6c/0x13f0
thread_imc_event_add+0xf4/0x1b0
event_sched_in+0xe0/0x210
merge_sched_in+0x1f0/0x600
visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
ctx_flexible_sched_in+0xcc/0x140
ctx_sched_in+0x20c/0x2a0
ctx_resched+0x104/0x1c0
perf_event_exec+0x340/0x510
begin_new_exec+0x730/0xef0
load_elf_binary+0x3f8/0x1e10
...
do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0
WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2)
MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000
CFAR: c00000000013fb64 IRQMASK: 1
The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.
Fix the issue by changing the mutex lock to spinlock.
Fixes: 8f95faaac5 ("powerpc/powernv: Detect and create IMC device")
Reported-by: Michael Petlan <mpetlan@redhat.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
[mpe: Fix comments, trim oops in change log, add reported-by tags]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
The ld_version() function computes the wrong version value for certain
ld versions such as the following:
$ ld --version
GNU ld (GNU Binutils; SUSE Linux Enterprise 15)
2.37.20211103-150100.7.37
For input 2.37.20211103, the value computed is 202348030000 which is
higher than the value for a later version like 2.39.0, which is
23900000.
This issue was highlighted because with the above ld version, the
powerpc kernel build started failing with ld error: "unrecognized option
--no-warn-rwx-segments". This was caused due to the recent commit
579aee9fc5 ("powerpc: suppress some linker warnings in recent linker
versions") which added the --no-warn-rwx-segments linker flag if the ld
version is greater than 2.39.
Due to the bug in ld_version(), ld version 2.37.20111103 is wrongly
calculated to be greater than 2.39 and the unsupported flag is added.
To fix it, if version is of the form x.y.z and length(z) == 8, then most
probably it is a date [yyyymmdd] commonly used for release snapshots and
not an actual new version. Hence, ignore the date part replacing it with
0.
Fixes: 579aee9fc5 ("powerpc: suppress some linker warnings in recent linker versions")
Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
[mpe: Tweak change log wording/formatting, add Fixes tag]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230104202437.90039-1-ojaswin@linux.ibm.com
Pull xtensa fixes from Max Filippov:
- fix xtensa allmodconfig build broken by the kcsan test
- drop unused members of struct thread_struct
* tag 'xtensa-20230110' of https://github.com/jcmvbkbc/linux-xtensa:
xtensa: drop unused members of struct thread_struct
kcsan: test: don't put the expect array on the stack
When creating a new monitoring group, the RMID allocated for it may have
been used by a group which was previously removed. In this case, the
hardware counters will have non-zero values which should be deducted
from what is reported in the new group's counts.
resctrl_arch_reset_rmid() initializes the prev_msr value for counters to
0, causing the initial count to be charged to the new group. Resurrect
__rmid_read() and use it to initialize prev_msr correctly.
Unlike before, __rmid_read() checks for error bits in the MSR read so
that callers don't need to.
Fixes: 1d81d15db3 ("x86/resctrl: Move mbm_overflow_count() into resctrl_arch_rmid_read()")
Signed-off-by: Peter Newman <peternewman@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20221220164132.443083-1-peternewman@google.com
When the user moves a running task to a new rdtgroup using the task's
file interface or by deleting its rdtgroup, the resulting change in
CLOSID/RMID must be immediately propagated to the PQR_ASSOC MSR on the
task(s) CPUs.
x86 allows reordering loads with prior stores, so if the task starts
running between a task_curr() check that the CPU hoisted before the
stores in the CLOSID/RMID update then it can start running with the old
CLOSID/RMID until it is switched again because __rdtgroup_move_task()
failed to determine that it needs to be interrupted to obtain the new
CLOSID/RMID.
Refer to the diagram below:
CPU 0 CPU 1
----- -----
__rdtgroup_move_task():
curr <- t1->cpu->rq->curr
__schedule():
rq->curr <- t1
resctrl_sched_in():
t1->{closid,rmid} -> {1,1}
t1->{closid,rmid} <- {2,2}
if (curr == t1) // false
IPI(t1->cpu)
A similar race impacts rdt_move_group_tasks(), which updates tasks in a
deleted rdtgroup.
In both cases, use smp_mb() to order the task_struct::{closid,rmid}
stores before the loads in task_curr(). In particular, in the
rdt_move_group_tasks() case, simply execute an smp_mb() on every
iteration with a matching task.
It is possible to use a single smp_mb() in rdt_move_group_tasks(), but
this would require two passes and a means of remembering which
task_structs were updated in the first loop. However, benchmarking
results below showed too little performance impact in the simple
approach to justify implementing the two-pass approach.
Times below were collected using `perf stat` to measure the time to
remove a group containing a 1600-task, parallel workload.
CPU: Intel(R) Xeon(R) Platinum P-8136 CPU @ 2.00GHz (112 threads)
# mkdir /sys/fs/resctrl/test
# echo $$ > /sys/fs/resctrl/test/tasks
# perf bench sched messaging -g 40 -l 100000
task-clock time ranges collected using:
# perf stat rmdir /sys/fs/resctrl/test
Baseline: 1.54 - 1.60 ms
smp_mb() every matching task: 1.57 - 1.67 ms
[ bp: Massage commit message. ]
Fixes: ae28d1aae4 ("x86/resctrl: Use an IPI instead of task_work_add() to update PQR_ASSOC MSR")
Fixes: 0efc89be94 ("x86/intel_rdt: Update task closid immediately on CPU in rmdir and unmount")
Signed-off-by: Peter Newman <peternewman@google.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20221220161123.432120-1-peternewman@google.com
Since
72cbc8f04f ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen")
PAT can be enabled without MTRR.
This has resulted in problems e.g. for a SEV-SNP guest running under Hyper-V,
when trying to establish a new mapping via memremap() with WB caching mode, as
pat_x_mtrr_type() will call mtrr_type_lookup(), which in turn is returning
MTRR_TYPE_INVALID due to MTRR being disabled in this configuration.
The result is a mapping with UC- caching, leading to severe performance
degradation.
Fix that by handling MTRR_TYPE_INVALID the same way as MTRR_TYPE_WRBACK
in pat_x_mtrr_type() because MTRR_TYPE_INVALID means MTRRs are disabled.
[ bp: Massage commit message. ]
Fixes: 72cbc8f04f ("x86/PAT: Have pat_enabled() properly reflect state when running on Xen")
Reported-by: Michael Kelley (LINUX) <mikelley@microsoft.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/20230110065427.20767-1-jgross@suse.com
This commit addresses the following erroneous situation with file-based
kdump executed on a system with a valid IPL report.
On s390, a kdump kernel, its initrd and IPL report if present are loaded
into a special and reserved on boot memory region - crashkernel. When
a system crashes and kdump was activated before, the purgatory code
is entered first which swaps the crashkernel and [0 - crashkernel size]
memory regions. Only after that the kdump kernel is entered. For this
reason, the pointer to an IPL report in lowcore must point to the IPL report
after the swap and not to the address of the IPL report that was located in
crashkernel memory region before the swap. Failing to do so, makes the
kdump's decompressor try to read memory from the crashkernel memory region
which already contains the production's kernel memory.
The situation described above caused spontaneous kdump failures/hangs
on systems where the Secure IPL is activated because on such systems
an IPL report is always present. In that case kdump's decompressor tried
to parse an IPL report which frequently lead to illegal memory accesses
because an IPL report contains addresses to various data.
Cc: <stable@vger.kernel.org>
Fixes: 99feaa717e ("s390/kexec_file: Create ipl report and pass to next kernel")
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
With 'GNU assembler (GNU Binutils for Debian) 2.39.90.20221231' the
build now reports:
arch/x86/realmode/rm/../../boot/bioscall.S: Assembler messages:
arch/x86/realmode/rm/../../boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/realmode/rm/../../boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/boot/bioscall.S: Assembler messages:
arch/x86/boot/bioscall.S:35: Warning: found `movsd'; assuming `movsl' was meant
arch/x86/boot/bioscall.S:70: Warning: found `movsd'; assuming `movsl' was meant
Which is due to:
PR gas/29525
Note that with the dropped CMPSD and MOVSD Intel Syntax string insn
templates taking operands, mixed IsString/non-IsString template groups
(with memory operands) cannot occur anymore. With that
maybe_adjust_templates() becomes unnecessary (and is hence being
removed).
More details: https://sourceware.org/bugzilla/show_bug.cgi?id=29525
Borislav Petkov further explains:
" the particular problem here is is that the 'd' suffix is
"conflicting" in the sense that you can have SSE mnemonics like movsD %xmm...
and the same thing also for string ops (which is the case here) so apparently
the agreement in binutils land is to use the always accepted suffixes 'l' or 'q'
and phase out 'd' slowly... "
Fixes: 7a734e7dd9 ("x86, setup: "glove box" BIOS calls -- infrastructure")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/Y71I3Ex2pvIxMpsP@hirez.programming.kicks-ass.net
commit 45bd895180 ("arm64: Improve HAVE_DYNAMIC_FTRACE_WITH_REGS
selection for clang") fixed the build with the above combination by
splitting HAVE_DYNAMIC_FTRACE_WITH_REGS into separate checks for
Clang and GCC.
commit 26299b3f6b ("ftrace: arm64: move from REGS to ARGS") added the
GCC only check "-fpatchable-function-entry=2" back in unconditionally
which breaks the build.
Remove the unconditional check, because the conditional ones were also
updated to _ARGS in the above commit, so they work correctly on their
own.
Fixes: 26299b3f6b ("ftrace: arm64: move from REGS to ARGS")
Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20230109122744.1904852-1-james.clark@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
With only two levels of page-table, the generic 'pud_*' macros are
implemented using dummy operations in pgtable-nopmd.h. Since commit
730a11f982 ("arm64/mm: add pud_user_exec() check in
pud_user_accessible_page()"), pud_user_accessible_page() unconditionally
calls pud_user_exec(), which is an arm64-specific helper and therefore
isn't defined by pgtable-nopmd.h. This results in a build failure for
configurations with only two levels of page table:
arch/arm64/include/asm/pgtable.h: In function 'pud_user_accessible_page':
>> arch/arm64/include/asm/pgtable.h:870:51: error: implicit declaration of function 'pud_user_exec'; did you mean 'pmd_user_exec'? [-Werror=implicit-function-declaration]
870 | return pud_leaf(pud) && (pud_user(pud) || pud_user_exec(pud));
| ^~~~~~~~~~~~~
| pmd_user_exec
Fix the problem by defining pud_user_exec() as pud_user() in this case.
Link: https://lore.kernel.org/r/202301080515.z6zEksU4-lkp@intel.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Will Deacon <will@kernel.org>
Since commit 80b6093b55 ("kbuild: add -Wundef to KBUILD_CPPFLAGS
for W=1 builds"), building with W=1 detects misuse of #(el)if.
$ make W=1 ARCH=s390 CROSS_COMPILE=s390x-linux-gnu-
[snip]
arch/s390/boot/decompressor.c:28:7: warning: "CONFIG_KERNEL_ZSTD" is not defined, evaluates to 0 [-Wundef]
28 | #elif CONFIG_KERNEL_ZSTD
| ^~~~~~~~~~~~~~~~~~
This issue has been hidden because arch/s390/boot/Makefile overwrites
KBUILD_CFLAGS, dropping -Wundef.
CONFIG_KERNEL_ZSTD is a bool option. #elif defined() should be used.
The line #ifdef CONFIG_KERNEL_BZIP2 is fine, but I changed it for
consistency.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20230106161024.2373602-1-masahiroy@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Add the missing #include of asm/assembler.h, which is where the ldr_l
macro is defined.
Fixes: ff7a167961 ("arm64: efi: Execute runtime services from a dedicated stack")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Passing the host topology to the guest is almost certainly wrong
and will confuse the scheduler. In addition, several fields of
these CPUID leaves vary on each processor; it is simply impossible to
return the right values from KVM_GET_SUPPORTED_CPUID in such a way that
they can be passed to KVM_SET_CPUID2.
The values that will most likely prevent confusion are all zeroes.
Userspace will have to override it anyway if it wishes to present a
specific topology to the guest.
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The mysterious comment "We only want the cr8 intercept bits of L1"
dates back to basically the introduction of nested SVM, back when
the handling of "less typical" hypervisors was very haphazard.
With the development of kvm-unit-tests for interrupt handling,
the same code grew another vmcb_clr_intercept for the interrupt
window (VINTR) vmexit, this time with a comment that is at least
decent.
It turns out however that the same comment applies to the CR8 write
intercept, which is also a "recheck if an interrupt should be
injected" intercept. The CR8 read intercept instead has not
been used by KVM for 14 years (commit 649d68643e, "KVM: SVM:
sync TPR value to V_TPR field in the VMCB"), so do not bother
clearing it and let one comment describe both CR8 write and VINTR
handling.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull powerpc fixes from Michael Ellerman:
- Three fixes for various bogosity in our linker script, revealed
by the recent commit which changed discard behaviour with some
toolchains.
* tag 'powerpc-6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/vmlinux.lds: Don't discard .comment
powerpc/vmlinux.lds: Don't discard .rela* for relocatable builds
powerpc/vmlinux.lds: Define RUNTIME_DISCARD_EXIT
Pull devicetree fixes from Rob Herring:
- Fix DT memory scanning for some MIPS boards when memory is not
specified in DT
- Redo CONFIG_CMDLINE* handling for missing /chosen node. The first
attempt broke PS3 (and possibly other PPC platforms).
- Fix constraints in QCom Soundwire schema
* tag 'devicetree-fixes-for-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2
Revert "of: fdt: Honor CONFIG_CMDLINE* even without /chosen node"
dt-bindings: soundwire: qcom,soundwire: correct sizes related to number of ports
of/fdt: run soc memory setup when early_init_dt_scan_memory fails
bad_vaddr, bad_uaddr and error_code fields are set but never read by the
xtensa arch-specific code. Drop them. Also drop the commented out info
field.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Pull arm TIF_NOTIFY_SIGNAL fixup from Jens Axboe:
"Hui Tang reported a performance regressions with _TIF_WORK_MASK in
newer kernels, which he tracked to a change that went into 5.11. After
this change, we'll call do_work_pending() more often than we need to,
because we're now testing bits 0..15 rather than just 0..7.
Shuffle the bits around to avoid this"
* tag 'tif-notify-signal-2023-01-06' of git://git.kernel.dk/linux:
ARM: renumber bits related to _TIF_WORK_MASK
Pull RISC-V fixes from Palmer Dabbelt:
- use the correct mask for c.jr/c.jalr when decoding instructions
- build fix for get_user() to avoid a sparse warning
* tag 'riscv-for-linus-6.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: uaccess: fix type of 0 variable on error in get_user()
riscv, kprobes: Stricter c.jr/c.jalr decoding
Pull perf fix from Ingo Molnar:
"Intel RAPL updates for new model IDs"
* tag 'perf-urgent-2023-01-06' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/rapl: Add support for Intel Emerald Rapids
perf/x86/rapl: Add support for Intel Meteor Lake
perf/x86/rapl: Treat Tigerlake like Icelake
Pull crypto fixes from Herbert Xu:
"This fixes a CFI crash in arm64/sm4 as well as a regression in the
caam driver"
* tag 'v6.2-p2' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: arm64/sm4 - fix possible crash with CFI enabled
crypto: caam - fix CAAM io mem access in blob_gen
If a Cortex-A715 cpu sees a page mapping permissions change from executable
to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers, on the
next instruction abort caused by permission fault.
Only user-space does executable to non-executable permission transition via
mprotect() system call which calls ptep_modify_prot_start() and ptep_modify
_prot_commit() helpers, while changing the page mapping. The platform code
can override these helpers via __HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION.
Work around the problem via doing a break-before-make TLB invalidation, for
all executable user space mappings, that go through mprotect() system call.
This overrides ptep_modify_prot_start() and ptep_modify_prot_commit(), via
defining HAVE_ARCH_PTEP_MODIFY_PROT_TRANSACTION on the platform thus giving
an opportunity to intercept user space exec mappings, and do the necessary
TLB invalidation. Similar interceptions are also implemented for HugeTLB.
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20230102061651.34745-1-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Nathan Chancellor reports that the s390 vmlinux fails to link with
GNU ld < 2.36 since commit 99cb0d917f ("arch: fix broken BuildID
for arm64 and riscv").
It happens for defconfig, or more specifically for CONFIG_EXPOLINE=y.
$ s390x-linux-gnu-ld --version | head -n1
GNU ld (GNU Binutils for Debian) 2.35.2
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- allnoconfig
$ ./scripts/config -e CONFIG_EXPOLINE
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu- olddefconfig
$ make -s ARCH=s390 CROSS_COMPILE=s390x-linux-gnu-
`.exit.text' referenced in section `.s390_return_reg' of drivers/base/dd.o: defined in discarded section `.exit.text' of drivers/base/dd.o
make[1]: *** [scripts/Makefile.vmlinux:34: vmlinux] Error 1
make: *** [Makefile:1252: vmlinux] Error 2
arch/s390/kernel/vmlinux.lds.S wants to keep EXIT_TEXT:
.exit.text : {
EXIT_TEXT
}
But, at the same time, EXIT_TEXT is thrown away by DISCARD because
s390 does not define RUNTIME_DISCARD_EXIT.
I still do not understand why the latter wins after 99cb0d917f,
but defining RUNTIME_DISCARD_EXIT seems correct because the comment
line in arch/s390/kernel/vmlinux.lds.S says:
/*
* .exit.text is discarded at runtime, not link time,
* to deal with references from __bug_table
*/
Nathan also found that binutils commit 21401fc7bf67 ("Duplicate output
sections in scripts") cured this issue, so we cannot reproduce it with
binutils 2.36+, but it is better to not rely on it.
Fixes: 99cb0d917f ("arch: fix broken BuildID for arm64 and riscv")
Link: https://lore.kernel.org/all/Y7Jal56f6UBh1abE@dev-arch.thelio-3990X/
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20230105031306.1455409-1-masahiroy@kernel.org
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
