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Linux kernel
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the problems which may result by upgrading your kernel.
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Pull irq fix from Thomas Gleixner:
"A single commit to handle an erratum in Cavium ThunderX to prevent
access to GIC registers which are broken in the implementation"
* tag 'irq-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Workaround Cavium erratum 38539 when reading GICD_TYPER2
Pull futex fix from Thomas Gleixner:
"Fix for yet another subtle futex issue.
The futex code used ihold() to prevent inodes from vanishing, but
ihold() does not guarantee inode persistence. Replace the inode
pointer with a per boot, machine wide, unique inode identifier.
The second commit fixes the breakage of the hash mechanism which
causes a 100% performance regression"
* tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Unbreak futex hashing
futex: Fix inode life-time issue
Pull irqchip fixes from Marc Zyngier:
- Add workaround for Cavium/Marvell ThunderX unimplemented GIC registers
Pull x86 fixes from Thomas Gleixner:
"Two fixes for x86:
- Map EFI runtime service data as encrypted when SEV is enabled.
Otherwise e.g. SMBIOS data cannot be properly decoded by dmidecode.
- Remove the warning in the vector management code which triggered
when a managed interrupt affinity changed outside of a CPU hotplug
operation.
The warning was correct until the recent core code change that
introduced a CPU isolation feature which needs to migrate managed
interrupts away from online CPUs under certain conditions to
achieve the isolation"
* tag 'x86-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vector: Remove warning on managed interrupt migration
x86/ioremap: Map EFI runtime services data as encrypted for SEV
The recent futex inode life time fix changed the ordering of the futex key
union struct members, but forgot to adjust the hash function accordingly,
As a result the hashing omits the leading 64bit and even hashes beyond the
futex key causing a bad hash distribution which led to a ~100% performance
regression.
Hand in the futex key pointer instead of a random struct member and make
the size calculation based of the struct offset.
Fixes: 8019ad13ef7f ("futex: Fix inode life-time issue")
Reported-by: Rong Chen <rong.a.chen@intel.com>
Decoded-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Rong Chen <rong.a.chen@intel.com>
Link: https://lkml.kernel.org/r/87h7yy90ve.fsf@nanos.tec.linutronix.de
This was noticed when printing debugfs for MSIs on my ARM64 server. The
new dstate IRQD_MSI_NOMASK_QUIRK came out surprisingly while it should only
be the x86 stuff for the time being...
The new MSI quirk flag uses the same bit as IRQ_DOMAIN_NAME_ALLOCATED which
is oddly defined as bit 6 for no good reason.
Switch it to the non used bit 1.
Fixes: 6f1a4891a592 ("x86/apic/msi: Plug non-maskable MSI affinity race")
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200221020725.2038-1-yuzenghui@huawei.com
Despite the architecture spec requiring that reserved registers in the GIC
distributor memory map are RES0 (and thus are not allowed to generate
an exception), the Cavium ThunderX (aka TX1) SoC explodes as such:
[ 0.000000] GICv3: GIC: Using split EOI/Deactivate mode
[ 0.000000] GICv3: 128 SPIs implemented
[ 0.000000] GICv3: 0 Extended SPIs implemented
[ 0.000000] Internal error: synchronous external abort: 96000210 [#1] SMP
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.0-rc4-00035-g3cf6a3d5725f #7956
[ 0.000000] Hardware name: cavium,thunder-88xx (DT)
[ 0.000000] pstate: 60000085 (nZCv daIf -PAN -UAO)
[ 0.000000] pc : __raw_readl+0x0/0x8
[ 0.000000] lr : gic_init_bases+0x110/0x560
[ 0.000000] sp : ffff800011243d90
[ 0.000000] x29: ffff800011243d90 x28: 0000000000000000
[ 0.000000] x27: 0000000000000018 x26: 0000000000000002
[ 0.000000] x25: ffff8000116f0000 x24: ffff000fbe6a2c80
[ 0.000000] x23: 0000000000000000 x22: ffff010fdc322b68
[ 0.000000] x21: ffff800010a7a208 x20: 00000000009b0404
[ 0.000000] x19: ffff80001124dad0 x18: 0000000000000010
[ 0.000000] x17: 000000004d8d492b x16: 00000000f67eb9af
[ 0.000000] x15: ffffffffffffffff x14: ffff800011249908
[ 0.000000] x13: ffff800091243ae7 x12: ffff800011243af4
[ 0.000000] x11: ffff80001126e000 x10: ffff800011243a70
[ 0.000000] x9 : 00000000ffffffd0 x8 : ffff80001069c828
[ 0.000000] x7 : 0000000000000059 x6 : ffff8000113fb4d1
[ 0.000000] x5 : 0000000000000001 x4 : 0000000000000000
[ 0.000000] x3 : 0000000000000000 x2 : 0000000000000000
[ 0.000000] x1 : 0000000000000000 x0 : ffff8000116f000c
[ 0.000000] Call trace:
[ 0.000000] __raw_readl+0x0/0x8
[ 0.000000] gic_of_init+0x188/0x224
[ 0.000000] of_irq_init+0x200/0x3cc
[ 0.000000] irqchip_init+0x1c/0x40
[ 0.000000] init_IRQ+0x160/0x1d0
[ 0.000000] start_kernel+0x2ec/0x4b8
[ 0.000000] Code: a8c47bfd d65f03c0 d538d080 d65f03c0 (b9400000)
when reading the GICv4.1 GICD_TYPER2 register, which is unexpected...
Work around it by adding a new quirk for the following variants:
ThunderX: CN88xx
OCTEON TX: CN83xx, CN81xx
OCTEON TX2: CN93xx, CN96xx, CN98xx, CNF95xx*
and use this flag to avoid accessing GICD_TYPER2. Note that all
reserved registers (including redistributors and ITS) are impacted
by this erratum, but that only GICD_TYPER2 has to be worked around
so far.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Robert Richter <rrichter@marvell.com>
Tested-by: Mark Salter <msalter@redhat.com>
Tested-by: Tim Harvey <tharvey@gateworks.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Robert Richter <rrichter@marvell.com>
Link: https://lore.kernel.org/r/20191027144234.8395-11-maz@kernel.org
Link: https://lore.kernel.org/r/20200311115649.26060-1-maz@kernel.org
Pull perf fixes from Thomas Gleixner:
"A pile of perf fixes:
Kernel side:
- AMD uncore driver: Replace the open coded sanity check with the
core variant, which provides the correct error code and also leaves
a hint in dmesg
Tooling:
- Fix the stdio input handling with glibc versions >= 2.28
- Unbreak the futex-wake benchmark which was reduced to 0 test
threads due to the conversion to cpumaps
- Initialize sigaction structs before invoking sys_sigactio()
- Plug the mapfile memory leak in perf jevents
- Fix off by one relative directory includes
- Fix an undefined string comparison in perf diff"
* tag 'perf-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/amd/uncore: Replace manual sampling check with CAP_NO_INTERRUPT flag
tools: Fix off-by 1 relative directory includes
perf jevents: Fix leak of mapfile memory
perf bench: Clear struct sigaction before sigaction() syscall
perf bench futex-wake: Restore thread count default to online CPU count
perf top: Fix stdio interface input handling with glibc 2.28+
perf diff: Fix undefined string comparision spotted by clang's -Wstring-compare
perf symbols: Don't try to find a vmlinux file when looking for kernel modules
perf bench: Share some global variables to fix build with gcc 10
perf parse-events: Use asprintf() instead of strncpy() to read tracepoint files
perf env: Do not return pointers to local variables
perf tests bp_account: Make global variable static
The vector management code assumes that managed interrupts cannot be
migrated away from an online CPU. free_moved_vector() has a WARN_ON_ONCE()
which triggers when a managed interrupt vector association on a online CPU
is cleared. The CPU offline code uses a different mechanism which cannot
trigger this.
This assumption is not longer correct because the new CPU isolation feature
which affects the placement of managed interrupts must be able to move a
managed interrupt away from an online CPU.
There are two reasons why this can happen:
1) When the interrupt is activated the affinity mask which was
established in irq_create_affinity_masks() is handed in to
the vector allocation code. This mask contains all CPUs to which
the interrupt can be made affine to, but this does not take the
CPU isolation 'managed_irq' mask into account.
When the interrupt is finally requested by the device driver then the
affinity is checked again and the CPU isolation 'managed_irq' mask is
taken into account, which moves the interrupt to a non-isolated CPU if
possible.
2) The interrupt can be affine to an isolated CPU because the
non-isolated CPUs in the calculated affinity mask are not online.
Once a non-isolated CPU which is in the mask comes online the
interrupt is migrated to this non-isolated CPU
In both cases the regular online migration mechanism is used which triggers
the WARN_ON_ONCE() in free_moved_vector().
Case #1 could have been addressed by taking the isolation mask into
account, but that would require a massive code change in the activation
logic and the eventual migration event was accepted as a reasonable
tradeoff when the isolation feature was developed. But even if #1 would be
addressed, #2 would still trigger it.
Of course the warning in free_moved_vector() was overlooked at that time
and the above two cases which have been discussed during patch review have
obviously never been tested before the final submission.
So keep it simple and remove the warning.
[ tglx: Rewrote changelog and added a comment to free_moved_vector() ]
Fixes: 11ea68f553e2 ("genirq, sched/isolation: Isolate from handling managed interrupts")
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lkml.kernel.org/r/20200312205830.81796-1-peterx@redhat.com
As reported by Jann, ihold() does not in fact guarantee inode
persistence. And instead of making it so, replace the usage of inode
pointers with a per boot, machine wide, unique inode identifier.
This sequence number is global, but shared (file backed) futexes are
rare enough that this should not become a performance issue.
Reported-by: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Qian Cai reported that the WARN_ON() in the x86/msi affinity setting code,
which catches cases where the affinity setting is not done on the CPU which
is the current target of the interrupt, triggers during CPU hotplug stress
testing.
It turns out that the warning which was added with the commit addressing
the MSI affinity race unearthed yet another long standing bug.
If user space writes a bogus affinity mask, i.e. it contains no online CPUs,
then it calls irq_select_affinity_usr(). This was introduced for ALPHA in
eee45269b0f5 ("[PATCH] Alpha: convert to generic irq framework (generic part)")
and subsequently made available for all architectures in
18404756765c ("genirq: Expose default irq affinity mask (take 3)")
which introduced the circumvention of the affinity setting restrictions for
interrupt which cannot be moved in process context.
The whole exercise is bogus in various aspects:
1) If the interrupt is already started up then there is absolutely
no point to honour a bogus interrupt affinity setting from user
space. The interrupt is already assigned to an online CPU and it
does not make any sense to reassign it to some other randomly
chosen online CPU.
2) If the interupt is not yet started up then there is no point
either. A subsequent startup of the interrupt will invoke
irq_setup_affinity() anyway which will chose a valid target CPU.
So the only correct solution is to just return -EINVAL in case user space
wrote an affinity mask which does not contain any online CPUs, except for
ALPHA which has it's own magic sauce for this.
Fixes: 18404756765c ("genirq: Expose default irq affinity mask (take 3)")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Qian Cai <cai@lca.pw>
Link: https://lkml.kernel.org/r/878sl8xdbm.fsf@nanos.tec.linutronix.de
V{PEND,PROP}BASER registers are actually located in VLPI_base frame
of the *redistributor*. Rename their accessors to reflect this fact.
No functional changes.
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200206075711.1275-7-yuzenghui@huawei.com
Pull timer fix from Thomas Gleixner:
"A single fix adding the missing time namespace adjustment in
sys/sysinfo which caused sys/sysinfo to be inconsistent with
/proc/uptime when read from a task inside a time namespace"
* tag 'timers-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sys/sysinfo: Respect boottime inside time namespace
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