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The per domain spinlock is acquired in iommu_flush_dev_iotlb(), which
is possbile to be called in the interrupt context. For example, the
drm-intel's CI system got completely blocked with below error:
WARNING: inconsistent lock state
6.0.0-rc1-CI_DRM_11990-g6590d43d39b9+ #1 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
swapper/6/0 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffff88810440d678 (&domain->lock){+.?.}-{2:2}, at: iommu_flush_dev_iotlb.part.61+0x23/0x80
{SOFTIRQ-ON-W} state was registered at:
lock_acquire+0xd3/0x310
_raw_spin_lock+0x2a/0x40
domain_update_iommu_cap+0x20b/0x2c0
intel_iommu_attach_device+0x5bd/0x860
__iommu_attach_device+0x18/0xe0
bus_iommu_probe+0x1f3/0x2d0
bus_set_iommu+0x82/0xd0
intel_iommu_init+0xe45/0x102a
pci_iommu_init+0x9/0x31
do_one_initcall+0x53/0x2f0
kernel_init_freeable+0x18f/0x1e1
kernel_init+0x11/0x120
ret_from_fork+0x1f/0x30
irq event stamp: 162354
hardirqs last enabled at (162354): [<ffffffff81b59274>] _raw_spin_unlock_irqrestore+0x54/0x70
hardirqs last disabled at (162353): [<ffffffff81b5901b>] _raw_spin_lock_irqsave+0x4b/0x50
softirqs last enabled at (162338): [<ffffffff81e00323>] __do_softirq+0x323/0x48e
softirqs last disabled at (162349): [<ffffffff810c1588>] irq_exit_rcu+0xb8/0xe0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&domain->lock);
<Interrupt>
lock(&domain->lock);
*** DEADLOCK ***
1 lock held by swapper/6/0:
This coverts the spin_lock/unlock() into the irq save/restore varieties
to fix the recursive locking issues.
Fixes: ffd5869d93530 ("iommu/vt-d: Replace spin_lock_irqsave() with spin_lock()")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20220817025650.3253959-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The Intel IOMMU driver possibly selects between the first-level and the
second-level translation tables for DMA address translation. However,
the levels of page-table walks for the 4KB base page size are calculated
from the SAGAW field of the capability register, which is only valid for
the second-level page table. This causes the IOMMU driver to stop working
if the hardware (or the emulated IOMMU) advertises only first-level
translation capability and reports the SAGAW field as 0.
This solves the above problem by considering both the first level and the
second level when calculating the supported page table levels.
Fixes: b802d070a52a1 ("iommu/vt-d: Use iova over first level")
Cc: stable@vger.kernel.org
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220817023558.3253263-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The translation table copying code for kdump kernels is currently based
on the extended root/context entry formats of ECS mode defined in older
VT-d v2.5, and doesn't handle the scalable mode formats. This causes
the kexec capture kernel boot failure with DMAR faults if the IOMMU was
enabled in scalable mode by the previous kernel.
The ECS mode has already been deprecated by the VT-d spec since v3.0 and
Intel IOMMU driver doesn't support this mode as there's no real hardware
implementation. Hence this converts ECS checking in copying table code
into scalable mode.
The existing copying code consumes a bit in the context entry as a mark
of copied entry. It needs to work for the old format as well as for the
extended context entries. As it's hard to find such a common bit for both
legacy and scalable mode context entries. This replaces it with a per-
IOMMU bitmap.
Fixes: 7373a8cc38197 ("iommu/vt-d: Setup context and enable RID2PASID support")
Cc: stable@vger.kernel.org
Reported-by: Jerry Snitselaar <jsnitsel@redhat.com>
Tested-by: Wen Jin <wen.jin@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220817011035.3250131-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
We started using a 64 bit completion value. Unfortunately, we only
stored the low 32-bits, so a very large completion value would never
be matched in iommu_completion_wait().
Fixes: c69d89aff393 ("iommu/amd: Use 4K page for completion wait write-back semaphore")
Signed-off-by: John Sperbeck <jsperbeck@google.com>
Link: https://lore.kernel.org/r/20220801192229.3358786-1-jsperbeck@google.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Pull powerpc fixes from Michael Ellerman:
- Fix handling of PCI domains in /proc on 32-bit systems using the
recently added support for numbering buses from zero for each domain.
- A fix and a revert for some changes to use READ/WRITE_ONCE() which
caused problems with KASAN enabled due to sanitisation calls being
introduced in low-level paths that can't cope with it.
- Fix build errors on 32-bit caused by the syscall table being
misaligned sometimes.
- Two fixes to get IBM Cell native machines booting again, which had
bit-rotted while my QS22 was temporarily out of action.
- Fix the papr_scm driver to not assume the order of events returned by
the hypervisor is stable, and a related compile fix.
Thanks to Aneesh Kumar K.V, Christophe Leroy, Jordan Niethe, Kajol Jain,
Masahiro Yamada, Nathan Chancellor, Pali Rohár, Vaibhav Jain, and Zhouyi
Zhou.
* tag 'powerpc-6.0-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/papr_scm: Ensure rc is always initialized in papr_scm_pmu_register()
Revert "powerpc/irq: Don't open code irq_soft_mask helpers"
powerpc: Fix hard_irq_disable() with sanitizer
powerpc/rtas: Fix RTAS MSR[HV] handling for Cell
Revert "powerpc: Remove unused FW_FEATURE_NATIVE references"
powerpc: align syscall table for ppc32
powerpc/pci: Enable PCI domains in /proc when PCI bus numbers are not unique
powerpc/papr_scm: Fix nvdimm event mappings
Pull kvm fixes from Paolo Bonzini:
"s390:
- PCI interpretation compile fixes
RISC-V:
- fix unused variable warnings in vcpu_timer.c
- move extern sbi_ext declarations to a header
x86:
- check validity of argument to KVM_SET_MP_STATE
- use guest's global_ctrl to completely disable guest PEBS
- fix a memory leak on memory allocation failure
- mask off unsupported and unknown bits of IA32_ARCH_CAPABILITIES
- fix build failure with Clang integrated assembler
- fix MSR interception
- always flush TLBs when enabling dirty logging"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: check validity of argument to KVM_SET_MP_STATE
perf/x86/core: Completely disable guest PEBS via guest's global_ctrl
KVM: x86: fix memoryleak in kvm_arch_vcpu_create()
KVM: x86: Mask off unsupported and unknown bits of IA32_ARCH_CAPABILITIES
KVM: s390: pci: Hook to access KVM lowlevel from VFIO
riscv: kvm: move extern sbi_ext declarations to a header
riscv: kvm: vcpu_timer: fix unused variable warnings
KVM: selftests: Fix ambiguous mov in KVM_ASM_SAFE()
KVM: selftests: Fix KVM_EXCEPTION_MAGIC build with Clang
KVM: VMX: Heed the 'msr' argument in msr_write_intercepted()
kvm: x86: mmu: Always flush TLBs when enabling dirty logging
kvm: x86: mmu: Drop the need_remote_flush() function
Clang warns:
arch/powerpc/platforms/pseries/papr_scm.c:492:6: warning: variable 'rc' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
if (!p->stat_buffer_len)
^~~~~~~~~~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:523:64: note: uninitialized use occurs here
dev_info(&p->pdev->dev, "nvdimm pmu didn't register rc=%d\n", rc);
^~
include/linux/dev_printk.h:150:67: note: expanded from macro 'dev_info'
dev_printk_index_wrap(_dev_info, KERN_INFO, dev, dev_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~
include/linux/dev_printk.h:110:23: note: expanded from macro 'dev_printk_index_wrap'
_p_func(dev, fmt, ##__VA_ARGS__); \
^~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:492:2: note: remove the 'if' if its condition is always false
if (!p->stat_buffer_len)
^~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/platforms/pseries/papr_scm.c:484:8: note: initialize the variable 'rc' to silence this warning
int rc, nodeid;
^
= 0
1 warning generated.
The call to papr_scm_pmu_check_events() was eliminated but a return code
was not added to the if statement. Add the same return code from
papr_scm_pmu_check_events() for this condition so there is no more
warning.
Fixes: 9b1ac04698a4 ("powerpc/papr_scm: Fix nvdimm event mappings")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://github.com/ClangBuiltLinux/linux/issues/1701
Link: https://lore.kernel.org/r/20220830151256.1473169-1-nathan@kernel.org
-Wformat was recently re-enabled for builds with clang, then quickly
re-disabled, due to concerns stemming from the frequency of default
argument promotion related warning instances.
commit 258fafcd0683 ("Makefile.extrawarn: re-enable -Wformat for clang")
commit 21f9c8a13bb2 ("Revert "Makefile.extrawarn: re-enable -Wformat for clang"")
ISO WG14 has ratified N2562 to address default argument promotion
explicitly for printf, as part of the upcoming ISO C2X standard.
The behavior of clang was changed in clang-16 to not warn for the cited
cases in all language modes.
Add a version check, so that users of clang-16 now get the full effect
of -Wformat. For older clang versions, re-enable flags under the
-Wformat group that way users still get some useful checks related to
format strings, without noisy default argument promotion warnings. I
intentionally omitted -Wformat-y2k and -Wformat-security from being
re-enabled, which are also part of -Wformat in clang-16.
Link: https://github.com/ClangBuiltLinux/linux/issues/378
Link: https://github.com/llvm/llvm-project/issues/57102
Link: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2562.pdf
Suggested-by: Justin Stitt <jstitt007@gmail.com>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Suggested-by: Youngmin Nam <youngmin.nam@samsung.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PCI interpretation compile fixes
This reverts commit ef5b570d3700fbb8628a58da0487486ceeb713cd.
Zhouyi reported that commit is causing crashes when running rcutorture
with KASAN enabled:
BUG: using smp_processor_id() in preemptible [00000000] code: rcu_torture_rea/100
caller is rcu_preempt_deferred_qs_irqrestore+0x74/0xed0
CPU: 4 PID: 100 Comm: rcu_torture_rea Tainted: G W 5.19.0-rc5-next-20220708-dirty #253
Call Trace:
dump_stack_lvl+0xbc/0x108 (unreliable)
check_preemption_disabled+0x154/0x160
rcu_preempt_deferred_qs_irqrestore+0x74/0xed0
__rcu_read_unlock+0x290/0x3b0
rcu_torture_read_unlock+0x30/0xb0
rcutorture_one_extend+0x198/0x810
rcu_torture_one_read+0x58c/0xc90
rcu_torture_reader+0x12c/0x360
kthread+0x1e8/0x220
ret_from_kernel_thread+0x5c/0x64
KASAN will generate instrumentation instructions around the
WRITE_ONCE(local_paca->irq_soft_mask, mask):
0xc000000000295cb0 <+0>: addis r2,r12,774
0xc000000000295cb4 <+4>: addi r2,r2,16464
0xc000000000295cb8 <+8>: mflr r0
0xc000000000295cbc <+12>: bl 0xc00000000008bb4c <mcount>
0xc000000000295cc0 <+16>: mflr r0
0xc000000000295cc4 <+20>: std r31,-8(r1)
0xc000000000295cc8 <+24>: addi r3,r13,2354
0xc000000000295ccc <+28>: mr r31,r13
0xc000000000295cd0 <+32>: std r0,16(r1)
0xc000000000295cd4 <+36>: stdu r1,-48(r1)
0xc000000000295cd8 <+40>: bl 0xc000000000609b98 <__asan_store1+8>
0xc000000000295cdc <+44>: nop
0xc000000000295ce0 <+48>: li r9,1
0xc000000000295ce4 <+52>: stb r9,2354(r31)
0xc000000000295ce8 <+56>: addi r1,r1,48
0xc000000000295cec <+60>: ld r0,16(r1)
0xc000000000295cf0 <+64>: ld r31,-8(r1)
0xc000000000295cf4 <+68>: mtlr r0
If there is a context switch before "stb r9,2354(r31)", r31 may
not equal to r13, in such case, irq soft mask will not work.
The usual solution of marking the code ineligible for instrumentation
forces the code out-of-line, which we would prefer to avoid. Christophe
proposed a partial revert, but Nick raised some concerns with that. So
for now do a full revert.
Reported-by: Zhouyi Zhou <zhouzhouyi@gmail.com>
[mpe: Construct change log based on Zhouyi's original report]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220831131052.42250-1-mpe@ellerman.id.au
Pull gpio fixes from Bartosz Golaszewski:
"A a set of fixes from the GPIO subsystem.
Most are small driver fixes except the realtek-otto driver patch which
is pretty big but addresses a significant flaw that can cause the CPU
to stay infinitely busy on uncleared ISR on some platforms.
Summary:
- MAINTAINERS update
- fix resource leaks in gpio-mockup and gpio-pxa
- add missing locking in gpio-pca953x
- use 32-bit I/O in gpio-realtek-otto
- make irq_chip structures immutable in four more drivers"
* tag 'gpio-fixes-for-v6.0-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux:
gpio: ws16c48: Make irq_chip immutable
gpio: 104-idio-16: Make irq_chip immutable
gpio: 104-idi-48: Make irq_chip immutable
gpio: 104-dio-48e: Make irq_chip immutable
gpio: realtek-otto: switch to 32-bit I/O
gpio: pca953x: Add mutex_lock for regcache sync in PM
gpio: mockup: remove gpio debugfs when remove device
gpio: pxa: use devres for the clock struct
MAINTAINERS: rectify entry for XILINX GPIO DRIVER
KVM/riscv fixes for 6.0, take #1
- Fix unused variable warnings in vcpu_timer.c
- Move extern sbi_ext declarations to a header
We have a cross dependency between KVM and VFIO when using
s390 vfio_pci_zdev extensions for PCI passthrough
To be able to keep both subsystem modular we add a registering
hook inside the S390 core code.
This fixes a build problem when VFIO is built-in and KVM is built
as a module.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop interpretive execution")
Cc: <stable@vger.kernel.org>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/r/20220819122945.9309-1-pmorel@linux.ibm.com
Message-Id: <20220819122945.9309-1-pmorel@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
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