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Linux kernel
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Pull scheduler fix from Borislav Petkov:
"A single fix to restore fairness between control groups with equal
priority"
* tag 'sched_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Correctly insert cfs_rq's to list on unthrottle
Pull irq fix from Borislav Petkov:
"A single fix for GICv3 to not take an interrupt in an NMI context"
* tag 'irq_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Workaround inconsistent PMR setting on NMI entry
Fix an issue where fairness is decreased since cfs_rq's can end up not
being decayed properly. For two sibling control groups with the same
priority, this can often lead to a load ratio of 99/1 (!!).
This happens because when a cfs_rq is throttled, all the descendant
cfs_rq's will be removed from the leaf list. When they initial cfs_rq
is unthrottled, it will currently only re add descendant cfs_rq's if
they have one or more entities enqueued. This is not a perfect
heuristic.
Instead, we insert all cfs_rq's that contain one or more enqueued
entities, or it its load is not completely decayed.
Can often lead to situations like this for equally weighted control
groups:
$ ps u -C stress
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 10009 88.8 0.0 3676 100 pts/1 R+ 11:04 0:13 stress --cpu 1
root 10023 3.0 0.0 3676 104 pts/1 R+ 11:04 0:00 stress --cpu 1
Fixes: 31bc6aeaab1d ("sched/fair: Optimize update_blocked_averages()")
[vingo: !SMP build fix]
Signed-off-by: Odin Ugedal <odin@uged.al>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20210612112815.61678-1-odin@uged.al
Pull x86 fixes from Borislav Petkov:
"A first set of urgent fixes to the FPU/XSTATE handling mess^W code.
(There's a lot more in the pipe):
- Prevent corruption of the XSTATE buffer in signal handling by
validating what is being copied from userspace first.
- Invalidate other task's preserved FPU registers on XRSTOR failure
(#PF) because latter can still modify some of them.
- Restore the proper PKRU value in case userspace modified it
- Reset FPU state when signal restoring fails
Other:
- Map EFI boot services data memory as encrypted in a SEV guest so
that the guest can access it and actually boot properly
- Two SGX correctness fixes: proper resources freeing and a NUMA fix"
* tag 'x86_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Avoid truncating memblocks for SGX memory
x86/sgx: Add missing xa_destroy() when virtual EPC is destroyed
x86/fpu: Reset state for all signal restore failures
x86/pkru: Write hardware init value to PKRU when xstate is init
x86/process: Check PF_KTHREAD and not current->mm for kernel threads
x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer
x86/fpu: Prevent state corruption in __fpu__restore_sig()
x86/ioremap: Map EFI-reserved memory as encrypted for SEV
Pull irqchip fixes from Marc Zyngier:
- Fix GICv3 NMI handling where an IRQ could be mistakenly handled
as a NMI, with disatrous effects
Link: https://lore.kernel.org/r/20210610171127.2404752-1-maz@kernel.org
Pull powerpc fixes from Michael Ellerman:
"Fix initrd corruption caused by our recent change to use relative jump
labels.
Fix a crash using perf record on systems without a hardware PMU
backend.
Rework our 64-bit signal handling slighty to make it more closely
match the old behaviour, after the recent change to use unsafe user
accessors.
Thanks to Anastasia Kovaleva, Athira Rajeev, Christophe Leroy, Daniel
Axtens, Greg Kurz, and Roman Bolshakov"
* tag 'powerpc-5.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf: Fix crash in perf_instruction_pointer() when ppmu is not set
powerpc: Fix initrd corruption with relative jump labels
powerpc/signal64: Copy siginfo before changing regs->nip
powerpc/mem: Add back missing header to fix 'no previous prototype' error
tl;dr:
Several SGX users reported seeing the following message on NUMA systems:
sgx: [Firmware Bug]: Unable to map EPC section to online node. Fallback to the NUMA node 0.
This turned out to be the memblock code mistakenly throwing away SGX
memory.
=== Full Changelog ===
The 'max_pfn' variable represents the highest known RAM address. It can
be used, for instance, to quickly determine for which physical addresses
there is mem_map[] space allocated. The numa_meminfo code makes an
effort to throw out ("trim") all memory blocks which are above 'max_pfn'.
SGX memory is not considered RAM (it is marked as "Reserved" in the
e820) and is not taken into account by max_pfn. Despite this, SGX memory
areas have NUMA affinity and are enumerated in the ACPI SRAT table. The
existing SGX code uses the numa_meminfo mechanism to look up the NUMA
affinity for its memory areas.
In cases where SGX memory was above max_pfn (usually just the one EPC
section in the last highest NUMA node), the numa_memblock is truncated
at 'max_pfn', which is below the SGX memory. When the SGX code tries to
look up the affinity of this memory, it fails and produces an error message:
sgx: [Firmware Bug]: Unable to map EPC section to online node. Fallback to the NUMA node 0.
and assigns the memory to NUMA node 0.
Instead of silently truncating the memory block at 'max_pfn' and
dropping the SGX memory, add the truncated portion to
'numa_reserved_meminfo'. This allows the SGX code to later determine
the NUMA affinity of its 'Reserved' area.
Before, numa_meminfo looked like this (from 'crash'):
blk = { start = 0x0, end = 0x2080000000, nid = 0x0 }
{ start = 0x2080000000, end = 0x4000000000, nid = 0x1 }
numa_reserved_meminfo is empty.
With this, numa_meminfo looks like this:
blk = { start = 0x0, end = 0x2080000000, nid = 0x0 }
{ start = 0x2080000000, end = 0x4000000000, nid = 0x1 }
and numa_reserved_meminfo has an entry for node 1's SGX memory:
blk = { start = 0x4000000000, end = 0x4080000000, nid = 0x1 }
[ daveh: completely rewrote/reworked changelog ]
Fixes: 5d30f92e7631 ("x86/NUMA: Provide a range-to-target_node lookup facility")
Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Fan Du <fan.du@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@intel.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20210617194657.0A99CB22@viggo.jf.intel.com
The arm64 entry code suffers from an annoying issue on taking
a NMI, as it sets PMR to a value that actually allows IRQs
to be acknowledged. This is done for consistency with other parts
of the code, and is in the process of being fixed. This shouldn't
be a problem, as we are not enabling interrupts whilst in NMI
context.
However, in the infortunate scenario that we took a spurious NMI
(retired before the read of IAR) *and* that there is an IRQ pending
at the same time, we'll ack the IRQ in NMI context. Too bad.
In order to avoid deadlocks while running something like perf,
teach the GICv3 driver about this situation: if we were in
a context where no interrupt should have fired, transiently
set PMR to a value that only allows NMIs before acking the pending
interrupt, and restore the original value after that.
This papers over the core issue for the time being, and makes
NMIs great again. Sort of.
Fixes: 4d6a38da8e79e94c ("arm64: entry: always set GIC_PRIO_PSR_I_SET during entry")
Co-developed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/lkml/20210610145731.1350460-1-maz@kernel.org
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Correct buffer copying when peeking events
- Sync cpufeatures/disabled-features.h header with the kernel sources
* tag 'perf-tools-fixes-for-v5.13-2021-06-13' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
tools headers cpufeatures: Sync with the kernel sources
perf session: Correct buffer copying when peeking events
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix refcount usage when processing PERF_RECORD_KSYMBOL.
- 'perf stat' metric group fixes.
- Fix 'perf test' non-bash issue with stat bpf counters.
- Update unistd, in.h and socket.h with the kernel sources, silencing
perf build warnings.
* tag 'perf-tools-fixes-for-v5.13-2021-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
tools headers UAPI: Sync linux/in.h copy with the kernel sources
tools headers UAPI: Sync asm-generic/unistd.h with the kernel original
perf beauty: Update copy of linux/socket.h with the kernel sources
perf test: Fix non-bash issue with stat bpf counters
perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL
perf metricgroup: Return error code from metricgroup__add_metric_sys_event_iter()
perf metricgroup: Fix find_evsel_group() event selector
On systems without any specific PMU driver support registered, running
perf record causes Oops.
The relevant portion from call trace:
BUG: Kernel NULL pointer dereference on read at 0x00000040
Faulting instruction address: 0xc0021f0c
Oops: Kernel access of bad area, sig: 11 [#1]
BE PAGE_SIZE=4K PREEMPT CMPCPRO
SAF3000 DIE NOTIFICATION
CPU: 0 PID: 442 Comm: null_syscall Not tainted 5.13.0-rc6-s3k-dev-01645-g7649ee3d2957 #5164
NIP: c0021f0c LR: c00e8ad8 CTR: c00d8a5c
NIP perf_instruction_pointer+0x10/0x60
LR perf_prepare_sample+0x344/0x674
Call Trace:
perf_prepare_sample+0x7c/0x674 (unreliable)
perf_event_output_forward+0x3c/0x94
__perf_event_overflow+0x74/0x14c
perf_swevent_hrtimer+0xf8/0x170
__hrtimer_run_queues.constprop.0+0x160/0x318
hrtimer_interrupt+0x148/0x3b0
timer_interrupt+0xc4/0x22c
Decrementer_virt+0xb8/0xbc
During perf record session, perf_instruction_pointer() is called to
capture the sample IP. This function in core-book3s accesses
ppmu->flags. If a platform specific PMU driver is not registered, ppmu
is set to NULL and accessing its members results in a crash. Fix this
crash by checking if ppmu is set.
Fixes: 2ca13a4cc56c ("powerpc/perf: Use regs->nip when SIAR is zero")
Cc: stable@vger.kernel.org # v5.11+
Reported-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1623952506-1431-1-git-send-email-atrajeev@linux.vnet.ibm.com
xa_destroy() needs to be called to destroy a virtual EPC's page array
before calling kfree() to free the virtual EPC. Currently it is not
called so add the missing xa_destroy().
Fixes: 540745ddbc70 ("x86/sgx: Introduce virtual EPC for use by KVM guests")
Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Tested-by: Yang Zhong <yang.zhong@intel.com>
Link: https://lkml.kernel.org/r/20210615101639.291929-1-kai.huang@intel.com
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