- 25 Aug, 2021 1 commit
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Nicolas Saenz Julienne authored
With the introduction of ee9707e8 ("cgroup/cpuset: Enable memory migration for cpuset v2") attaching a process to a different cgroup will trigger a memory migration regardless of whether it's really needed. Memory migration is an expensive operation, so bypass it if the nodemasks passed to cpuset_migrate_mm() are equal. Note that we're not only avoiding the migration work itself, but also a call to lru_cache_disable(), which triggers and flushes an LRU drain work on every online CPU. Signed-off-by:
Nicolas Saenz Julienne <nsaenzju@redhat.com> Signed-off-by:
Tejun Heo <tj@kernel.org>
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- 12 Aug, 2021 1 commit
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Waiman Long authored
When a user changes cpuset.cpus, each task in a v2 cpuset will be moved to one of the new cpus if it is not there already. For memory, however, they won't be migrated to the new nodes when cpuset.mems changes. This is an inconsistency in behavior. In cpuset v1, there is a memory_migrate control file to enable such behavior by setting the CS_MEMORY_MIGRATE flag. Make it the default for cpuset v2 so that we have a consistent set of behavior for both cpus and memory. There is certainly a cost to make memory migration the default, but it is a one time cost that shouldn't really matter as long as cpuset.mems isn't changed frequenty. Update the cgroup-v2.rst file to document the new behavior and recommend against changing cpuset.mems frequently. Since there won't be any concurrent access to the newly allocated cpuset structure in cpuset_css_alloc(), we can use the cheaper non-atomic __set_bit() instead of the more expensive atomic set_bit(). Signed-off-by:
Waiman Long <longman@redhat.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Signed-off-by:
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- 11 Aug, 2021 2 commits
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Waiman Long authored
A valid cpuset partition can become invalid if all its CPUs are offlined or somehow removed. This can happen through external events without "cpuset.cpus.partition" being touched at all. Users that rely on the property of a partition being present do not currently have a simple way to get such an event notified other than constant periodic polling which is both inefficient and cumbersome. To make life easier for those users, event notification is now enabled for "cpuset.cpus.partition" whenever its state changes. Suggested-by:
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Randy Dunlap authored
Fix kernel-doc warnings found in cgroup-v1.c: kernel/cgroup/cgroup-v1.c:55: warning: No description found for return value of 'cgroup_attach_task_all' kernel/cgroup/cgroup-v1.c:94: warning: expecting prototype for cgroup_trasnsfer_tasks(). Prototype was for cgroup_transfer_tasks() instead cgroup-v1.c:96: warning: No description found for return value of 'cgroup_transfer_tasks' kernel/cgroup/cgroup-v1.c:687: warning: No description found for return value of 'cgroupstats_build' Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org Signed-off-by:
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- 09 Aug, 2021 2 commits
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Sebastian Andrzej Siewior authored
The functions get_online_cpus() and put_online_cpus() have been deprecated during the CPU hotplug rework. They map directly to cpus_read_lock() and cpus_read_unlock(). Replace deprecated CPU-hotplug functions with the official version. The behavior remains unchanged. Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: cgroups@vger.kernel.org Signed-off-by:
Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by:
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Waiman Long authored
The cpuset fields that manage partition root state do not strictly follow the cpuset locking rule that update to cpuset has to be done with both the callback_lock and cpuset_mutex held. This is now fixed by making sure that the locking rule is upheld. Fixes: 3881b861 ("cpuset: Add an error state to cpuset.sched.partition") Fixes: 4b842da2 ("cpuset: Make CPU hotplug work with partition") Signed-off-by:
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- 26 Jul, 2021 2 commits
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Waiman Long authored
In cpuset_hotplug_workfn(), the detection of whether the cpu list has been changed is done by comparing the effective cpus of the top cpuset with the cpu_active_mask. However, in the rare case that just all the CPUs in the subparts_cpus are offlined, the detection fails and the partition states are not updated correctly. Fix it by forcing the cpus_updated flag to true in this particular case. Fixes: 4b842da2 ("cpuset: Make CPU hotplug work with partition") Signed-off-by:
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Waiman Long authored
Use more descriptive variable names for update_prstate(), remove unnecessary code and fix some typos. There is no functional change. Signed-off-by:
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- 16 Jul, 2021 4 commits
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zhaoxiaoqiang11 authored
Git rid of an outdated comment. Since cgroup was fully switched to fs_context, cgroup_mount() is gone and it's confusing to mention in comments of cgroup_kill_sb(). Delete it. Signed-off-by:
zhaoxiaoqiang11 <zhaoxiaoqiang11@jd.com> Signed-off-by:
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Linus Torvalds authored
This reverts commit b7eb335e. It turns out that the problem with the clang -Wimplicit-fallthrough warning is not about the kernel source code, but about clang itself, and that the warning is unusable until clang fixes its broken ways. In particular, when you enable this warning for clang, you not only get warnings about implicit fallthroughs. You also get this: warning: fallthrough annotation in unreachable code [-Wimplicit-fallthrough] which is completely broken becasue it (a) doesn't even tell you where the problem is (seriously: no line numbers, no filename, no nothing). (b) is fundamentally broken anyway, because there are perfectly valid reasons to have a fallthrough statement even if it turns out that it can perhaps not be reached. In the kernel, an example of that second case is code in the scheduler: switch (state) { case cpuset: if (IS_ENABLED(CONFIG_CPUSETS)) { cpuset_cpus_allowed_fallback(p); state = possible; break; } fallthrough; case possible: where if CONFIG_CPUSETS is enabled you actually never hit the fallthrough case at all. But that in no way makes the fallthrough wrong. So the warning is completely broken, and enabling it for clang is a very bad idea. In the meantime, we can keep the gcc option enabled, and make the gcc build use -Wimplicit-fallthrough=5 which means that we will at least continue to require a proper fallthrough statement, and that gcc won't silently accept the magic comment versions. Because gcc does this all correctly, and while the odd "=5" part is kind of obscure, it's documented in [1]: "-Wimplicit-fallthrough=5 doesn’t recognize any comments as fallthrough comments, only attributes disable the warning" so if clang ever fixes its bad behavior we can try enabling it there again. Link: https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html [1] Cc: Kees Cook <keescook@chromium.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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git://git.infradead.org/users/hch/configfsLinus Torvalds authored
Pull configfs fix from Christoph Hellwig: - fix the read and write iterators (Bart Van Assche) * tag 'configfs-5.13-1' of git://git.infradead.org/users/hch/configfs: configfs: fix the read and write iterators
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Linus Torvalds authored
Merge tag 'pwm/for-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm Pull pwm fixes from Thierry Reding: "A couple of fixes from Uwe that I missed for v5.14-rc1" * tag 'pwm/for-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: pwm: ep93xx: Ensure configuring period and duty_cycle isn't wrongly skipped pwm: berlin: Ensure configuring period and duty_cycle isn't wrongly skipped pwm: tiecap: Ensure configuring period and duty_cycle isn't wrongly skipped pwm: spear: Ensure configuring period and duty_cycle isn't wrongly skipped pwm: sprd: Ensure configuring period and duty_cycle isn't wrongly skipped
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- 15 Jul, 2021 28 commits
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Linus Torvalds authored
Merge tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux Pull fallthrough fixes from Gustavo Silva: "This fixes many fall-through warnings when building with Clang and -Wimplicit-fallthrough, and also enables -Wimplicit-fallthrough for Clang, globally. It's also important to notice that since we have adopted the use of the pseudo-keyword macro fallthrough, we also want to avoid having more /* fall through */ comments being introduced. Contrary to GCC, Clang doesn't recognize any comments as implicit fall-through markings when the -Wimplicit-fallthrough option is enabled. So, in order to avoid having more comments being introduced, we use the option -Wimplicit-fallthrough=5 for GCC, which similar to Clang, will cause a warning in case a code comment is intended to be used as a fall-through marking. The patch for Makefile also enforces this. We had almost 4,000 of these issues for Clang in the beginning, and there might be a couple more out there when building some architectures with certain configurations. However, with the recent fixes I think we are in good shape and it is now possible to enable the warning for Clang" * tag 'Wimplicit-fallthrough-clang-5.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (27 commits) Makefile: Enable -Wimplicit-fallthrough for Clang powerpc/smp: Fix fall-through warning for Clang dmaengine: mpc512x: Fix fall-through warning for Clang usb: gadget: fsl_qe_udc: Fix fall-through warning for Clang powerpc/powernv: Fix fall-through warning for Clang MIPS: Fix unreachable code issue MIPS: Fix fall-through warnings for Clang ASoC: Mediatek: MT8183: Fix fall-through warning for Clang power: supply: Fix fall-through warnings for Clang dmaengine: ti: k3-udma: Fix fall-through warning for Clang s390: Fix fall-through warnings for Clang dmaengine: ipu: Fix fall-through warning for Clang iommu/arm-smmu-v3: Fix fall-through warning for Clang mmc: jz4740: Fix fall-through warning for Clang PCI: Fix fall-through warning for Clang scsi: libsas: Fix fall-through warning for Clang video: fbdev: Fix fall-through warning for Clang math-emu: Fix fall-through warning cpufreq: Fix fall-through warning for Clang drm/msm: Fix fall-through warning in msm_gem_new_impl() ...
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Linus Torvalds authored
Merge misc fixes from Andrew Morton: "13 patches. Subsystems affected by this patch series: mm (kasan, pagealloc, rmap, hmm, and hugetlb), and hfs" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm/hugetlb: fix refs calculation from unaligned @vaddr hfs: add lock nesting notation to hfs_find_init hfs: fix high memory mapping in hfs_bnode_read hfs: add missing clean-up in hfs_fill_super lib/test_hmm: remove set but unused page variable mm: fix the try_to_unmap prototype for !CONFIG_MMU mm/page_alloc: further fix __alloc_pages_bulk() return value mm/page_alloc: correct return value when failing at preparing mm/page_alloc: avoid page allocator recursion with pagesets.lock held Revert "mm/page_alloc: make should_fail_alloc_page() static" kasan: fix build by including kernel.h kasan: add memzero init for unaligned size at DEBUG mm: move helper to check slub_debug_enabled
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Randy Dunlap authored
My previous patch had a typo/thinko which prevents this driver from being enabled: change X64_64 to X86_64. Fixes: 0a9ece9b ("EDAC/igen6: fix core dependency") Signed-off-by:
Tony Luck <tony.luck@intel.com> Signed-off-by:
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git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds authored
Pull kvm fixes from Paolo Bonzini: - Allow again loading KVM on 32-bit non-PAE builds - Fixes for host SMIs on AMD - Fixes for guest SMIs on AMD - Fixes for selftests on s390 and ARM - Fix memory leak - Enforce no-instrumentation area on vmentry when hardware breakpoints are in use. * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits) KVM: selftests: smm_test: Test SMM enter from L2 KVM: nSVM: Restore nested control upon leaving SMM KVM: nSVM: Fix L1 state corruption upon return from SMM KVM: nSVM: Introduce svm_copy_vmrun_state() KVM: nSVM: Check that VM_HSAVE_PA MSR was set before VMRUN KVM: nSVM: Check the value written to MSR_VM_HSAVE_PA KVM: SVM: Fix sev_pin_memory() error checks in SEV migration utilities KVM: SVM: Return -EFAULT if copy_to_user() for SEV mig packet header fails KVM: SVM: add module param to control the #SMI interception KVM: SVM: remove INIT intercept handler KVM: SVM: #SMI interception must not skip the instruction KVM: VMX: Remove vmx_msr_index from vmx.h KVM: X86: Disable hardware breakpoints unconditionally before kvm_x86->run() KVM: selftests: Address extra memslot parameters in vm_vaddr_alloc kvm: debugfs: fix memory leak in kvm_create_vm_debugfs KVM: x86/pmu: Clear anythread deprecated bit when 0xa leaf is unsupported on the SVM KVM: mmio: Fix use-after-free Read in kvm_vm_ioctl_unregister_coalesced_mmio KVM: SVM: Revert clearing of C-bit on GPA in #NPF handler KVM: x86/mmu: Do not apply HPA (memory encryption) mask to GPAs KVM: x86: Use kernel's x86_phys_bits to handle reduced MAXPHYADDR ...
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git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommuLinus Torvalds authored
Pull iommu fixes from Joerg Roedel: - Revert a patch which caused boot failures with QCOM IOMMU - Two fixes for Intel VT-d context table handling - Physical address decoding fix for Rockchip IOMMU - Add a reviewer for AMD IOMMU * tag 'iommu-fixes-v5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: MAINTAINERS: Add Suravee Suthikulpanit as Reviewer for AMD IOMMU (AMD-Vi) iommu/rockchip: Fix physical address decoding iommu/vt-d: Fix clearing real DMA device's scalable-mode context entries iommu/vt-d: Global devTLB flush when present context entry changed iommu/qcom: Revert "iommu/arm: Cleanup resources in case of probe error path"
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Joao Martins authored
Commit 82e5d378 ("mm/hugetlb: refactor subpage recording") refactored the count of subpages but missed an edge case when @vaddr is not aligned to PAGE_SIZE e.g. when close to vma->vm_end. It would then errousnly set @refs to 0 and record_subpages_vmas() wouldn't set the @pages array element to its value, consequently causing the reported null-deref by syzbot. Fix it by aligning down @vaddr by PAGE_SIZE in @refs calculation. Link: https://lkml.kernel.org/r/20210713152440.28650-1-joao.m.martins@oracle.com Fixes: 82e5d378 ("mm/hugetlb: refactor subpage recording") Reported-by: syzbot+a3fcd59df1b372066f5a@syzkaller.appspotmail.com Signed-off-by:
Joao Martins <joao.m.martins@oracle.com> Reviewed-by:
Mike Kravetz <mike.kravetz@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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Desmond Cheong Zhi Xi authored
Syzbot reports a possible recursive lock in [1]. This happens due to missing lock nesting information. From the logs, we see that a call to hfs_fill_super is made to mount the hfs filesystem. While searching for the root inode, the lock on the catalog btree is grabbed. Then, when the parent of the root isn't found, a call to __hfs_bnode_create is made to create the parent of the root. This eventually leads to a call to hfs_ext_read_extent which grabs a lock on the extents btree. Since the order of locking is catalog btree -> extents btree, this lock hierarchy does not lead to a deadlock. To tell lockdep that this locking is safe, we add nesting notation to distinguish between catalog btrees, extents btrees, and attributes btrees (for HFS+). This has already been done in hfsplus. Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1] Link: https://lkml.kernel.org/r/20210701030756.58760-4-desmondcheongzx@gmail.comSigned-off-by:
Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Reported-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com Tested-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com Reviewed-by:
Viacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Gustavo A. R. Silva <gustavoars@kernel.org> Cc: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by:
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Desmond Cheong Zhi Xi authored
Pages that we read in hfs_bnode_read need to be kmapped into kernel address space. However, currently only the 0th page is kmapped. If the given offset + length exceeds this 0th page, then we have an invalid memory access. To fix this, we kmap relevant pages one by one and copy their relevant portions of data. An example of invalid memory access occurring without this fix can be seen in the following crash report: ================================================================== BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline] BUG: KASAN: use-after-free in hfs_bnode_read+0xc4/0xe0 fs/hfs/bnode.c:26 Read of size 2 at addr ffff888125fdcffe by task syz-executor5/4634 CPU: 0 PID: 4634 Comm: syz-executor5 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x195/0x1f8 lib/dump_stack.c:120 print_address_description.constprop.0+0x1d/0x110 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7b/0xd4 mm/kasan/report.c:436 check_region_inline mm/kasan/generic.c:180 [inline] kasan_check_range+0x154/0x1b0 mm/kasan/generic.c:186 memcpy+0x24/0x60 mm/kasan/shadow.c:65 memcpy include/linux/fortify-string.h:191 [inline] hfs_bnode_read+0xc4/0xe0 fs/hfs/bnode.c:26 hfs_bnode_read_u16 fs/hfs/bnode.c:34 [inline] hfs_bnode_find+0x880/0xcc0 fs/hfs/bnode.c:365 hfs_brec_find+0x2d8/0x540 fs/hfs/bfind.c:126 hfs_brec_read+0x27/0x120 fs/hfs/bfind.c:165 hfs_cat_find_brec+0x19a/0x3b0 fs/hfs/catalog.c:194 hfs_fill_super+0xc13/0x1460 fs/hfs/super.c:419 mount_bdev+0x331/0x3f0 fs/super.c:1368 hfs_mount+0x35/0x40 fs/hfs/super.c:457 legacy_get_tree+0x10c/0x220 fs/fs_context.c:592 vfs_get_tree+0x93/0x300 fs/super.c:1498 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x13f5/0x20e0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount fs/namespace.c:3433 [inline] __x64_sys_mount+0x2b8/0x340 fs/namespace.c:3433 do_syscall_64+0x37/0xc0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x45e63a Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 88 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9404d410d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000248 RCX: 000000000045e63a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f9404d41120 RBP: 00007f9404d41120 R08: 00000000200002c0 R09: 0000000020000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 R13: 0000000000000003 R14: 00000000004ad5d8 R15: 0000000000000000 The buggy address belongs to the page: page:00000000dadbcf3e refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x125fdc flags: 0x2fffc0000000000(node=0|zone=2|lastcpupid=0x3fff) raw: 02fffc0000000000 ffffea000497f748 ffffea000497f6c8 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888125fdce80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888125fdcf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888125fdcf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888125fdd000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888125fdd080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== Link: https://lkml.kernel.org/r/20210701030756.58760-3-desmondcheongzx@gmail.comSigned-off-by: -
Desmond Cheong Zhi Xi authored
Patch series "hfs: fix various errors", v2. This series ultimately aims to address a lockdep warning in hfs_find_init reported by Syzbot [1]. The work done for this led to the discovery of another bug, and the Syzkaller repro test also reveals an invalid memory access error after clearing the lockdep warning. Hence, this series is broken up into three patches: 1. Add a missing call to hfs_find_exit for an error path in hfs_fill_super 2. Fix memory mapping in hfs_bnode_read by fixing calls to kmap 3. Add lock nesting notation to tell lockdep that the observed locking hierarchy is safe This patch (of 3): Before exiting hfs_fill_super, the struct hfs_find_data used in hfs_find_init should be passed to hfs_find_exit to be cleaned up, and to release the lock held on the btree. The call to hfs_find_exit is missing from an error path. We add it back in by consolidating calls to hfs_find_exit for error paths. Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1] Link: https://lkml.kernel.org/r/20210701030756.58760-1-desmondcheongzx@gmail.com Link: https://lkml.kernel.org/r/20210701030756.58760-2-desmondcheongzx@gmail.comSigned-off-by:
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Alistair Popple authored
The HMM selftests use atomic_check_access() to check atomic access to a page has been revoked. It doesn't matter if the page mapping has been removed from the mirrored page tables as that also implies atomic access has been revoked. Therefore remove the unused page variable to fix this compiler warning: lib/test_hmm.c:631:16: warning: variable `page' set but not used [-Wunused-but-set-variable] Link: https://lkml.kernel.org/r/20210706025603.4059-1-apopple@nvidia.com Fixes: b659baea ("mm: selftests for exclusive device memory") Signed-off-by:
Alistair Popple <apopple@nvidia.com> Reported-by:
Hulk Robot <hulkci@huawei.com> Reported-by:
kernel test robot <oliver.sang@intel.com> Reported-by:
Yang Yingliang <yangyingliang@huawei.com> Acked-by:
Souptick Joarder <jrdr.linux@gmail.com> Signed-off-by:
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Christoph Hellwig authored
Adjust the nommu stub of try_to_unmap to match the changed protype for the full version. Turn it into an inline instead of a macro to generally improve the type checking. Link: https://lkml.kernel.org/r/20210705053944.885828-1-hch@lst.de Fixes: 1fb08ac6 ("mm: rmap: make try_to_unmap() void function") Signed-off-by:
Christoph Hellwig <hch@lst.de> Reviewed-by:
Yang Shi <shy828301@gmail.com> Signed-off-by:
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Chuck Lever authored
The author of commit b3b64ebd ("mm/page_alloc: do bulk array bounds check after checking populated elements") was possibly confused by the mixture of return values throughout the function. The API contract is clear that the function "Returns the number of pages on the list or array." It does not list zero as a unique return value with a special meaning. Therefore zero is a plausible return value only if @nr_pages is zero or less. Clean up the return logic to make it clear that the returned value is always the total number of pages in the array/list, not the number of pages that were allocated during this call. The only change in behavior with this patch is the value returned if prepare_alloc_pages() fails. To match the API contract, the number of pages currently in the array/list is returned in this case. The call site in __page_pool_alloc_pages_slow() also seems to be confused on this matter. It should be attended to by someone who is familiar with that code. [mel@techsingularity.net: Return nr_populated if 0 pages are requested] Link: https://lkml.kernel.org/r/20210713152100.10381-4-mgorman@techsingularity.netSigned-off-by:
Chuck Lever <chuck.lever@oracle.com> Signed-off-by:
Mel Gorman <mgorman@techsingularity.net> Acked-by:
Jesper Dangaard Brouer <brouer@redhat.com> Cc: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com> Cc: Zhang Qiang <Qiang.Zhang@windriver.com> Cc: Yanfei Xu <yanfei.xu@windriver.com> Cc: Matteo Croce <mcroce@microsoft.com> Signed-off-by:
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Yanfei Xu authored
If the array passed in is already partially populated, we should return "nr_populated" even failing at preparing arguments stage. Link: https://lkml.kernel.org/r/20210713152100.10381-3-mgorman@techsingularity.netSigned-off-by:
Yanfei Xu <yanfei.xu@windriver.com> Signed-off-by:
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Mel Gorman authored
Syzbot is reporting potential deadlocks due to pagesets.lock when PAGE_OWNER is enabled. One example from Desmond Cheong Zhi Xi is as follows __alloc_pages_bulk() local_lock_irqsave(&pagesets.lock, flags) <---- outer lock here prep_new_page(): post_alloc_hook(): set_page_owner(): __set_page_owner(): save_stack(): stack_depot_save(): alloc_pages(): alloc_page_interleave(): __alloc_pages(): get_page_from_freelist(): rm_queue(): rm_queue_pcplist(): local_lock_irqsave(&pagesets.lock, flags); *** DEADLOCK *** Zhang, Qiang also reported BUG: sleeping function called from invalid context at mm/page_alloc.c:5179 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0 ..... __dump_stack lib/dump_stack.c:79 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96 ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9153 prepare_alloc_pages+0x3da/0x580 mm/page_alloc.c:5179 __alloc_pages+0x12f/0x500 mm/page_alloc.c:5375 alloc_page_interleave+0x1e/0x200 mm/mempolicy.c:2147 alloc_pages+0x238/0x2a0 mm/mempolicy.c:2270 stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303 save_stack+0x15e/0x1e0 mm/page_owner.c:120 __set_page_owner+0x50/0x290 mm/page_owner.c:181 prep_new_page mm/page_alloc.c:2445 [inline] __alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5313 alloc_pages_bulk_array_node include/linux/gfp.h:557 [inline] vm_area_alloc_pages mm/vmalloc.c:2775 [inline] __vmalloc_area_node mm/vmalloc.c:2845 [inline] __vmalloc_node_range+0x39d/0x960 mm/vmalloc.c:2947 __vmalloc_node mm/vmalloc.c:2996 [inline] vzalloc+0x67/0x80 mm/vmalloc.c:3066 There are a number of ways it could be fixed. The page owner code could be audited to strip GFP flags that allow sleeping but it'll impair the functionality of PAGE_OWNER if allocations fail. The bulk allocator could add a special case to release/reacquire the lock for prep_new_page and lookup PCP after the lock is reacquired at the cost of performance. The pages requiring prep could be tracked using the least significant bit and looping through the array although it is more complicated for the list interface. The options are relatively complex and the second one still incurs a performance penalty when PAGE_OWNER is active so this patch takes the simple approach -- disable bulk allocation of PAGE_OWNER is active. The caller will be forced to allocate one page at a time incurring a performance penalty but PAGE_OWNER is already a performance penalty. Link: https://lkml.kernel.org/r/20210708081434.GV3840@techsingularity.net Fixes: dbbee9d5 ("mm/page_alloc: convert per-cpu list protection to local_lock") Signed-off-by:"Zhang, Qiang" <Qiang.Zhang@windriver.com> Reported-by: syzbot+127fd7828d6eeb611703@syzkaller.appspotmail.com Tested-by: syzbot+127fd7828d6eeb611703@syzkaller.appspotmail.com Acked-by:
Rafael Aquini <aquini@redhat.com> Cc: Shuah Khan <skhan@linuxfoundation.org> Signed-off-by:
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Matteo Croce authored
This reverts commit f7173090. Fix an unresolved symbol error when CONFIG_DEBUG_INFO_BTF=y: LD vmlinux BTFIDS vmlinux FAILED unresolved symbol should_fail_alloc_page make: *** [Makefile:1199: vmlinux] Error 255 make: *** Deleting file 'vmlinux' Link: https://lkml.kernel.org/r/20210708191128.153796-1-mcroce@linux.microsoft.com Fixes: f7173090 ("mm/page_alloc: make should_fail_alloc_page() static") Signed-off-by:
Matteo Croce <mcroce@microsoft.com> Acked-by:
John Hubbard <jhubbard@nvidia.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Streetman <ddstreet@ieee.org> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by:
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Marco Elver authored
The <linux/kasan.h> header relies on _RET_IP_ being defined, and had been receiving that definition via inclusion of bug.h which includes kernel.h. However, since f39650de ("kernel.h: split out panic and oops helpers") that is no longer the case and get the following build error when building CONFIG_KASAN_HW_TAGS on arm64: In file included from arch/arm64/mm/kasan_init.c:10: include/linux/kasan.h: In function 'kasan_slab_free': include/linux/kasan.h:230:39: error: '_RET_IP_' undeclared (first use in this function) 230 | return __kasan_slab_free(s, object, _RET_IP_, init); Fix it by including kernel.h from kasan.h. Link: https://lkml.kernel.org/r/20210705072716.2125074-1-elver@google.com Fixes: f39650de ("kernel.h: split out panic and oops helpers") Signed-off-by:
Marco Elver <elver@google.com> Reviewed-by:
Andy Shevchenko <andy.shevchenko@gmail.com> Reviewed-by:
Andrey Konovalov <andreyknvl@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Peter Collingbourne <pcc@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Signed-off-by:
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Yee Lee authored
Issue: when SLUB debug is on, hwtag kasan_unpoison() would overwrite the redzone of object with unaligned size. An additional memzero_explicit() path is added to replacing init by hwtag instruction for those unaligned size at SLUB debug mode. The penalty is acceptable since they are only enabled in debug mode, not production builds. A block of comment is added for explanation. Link: https://lkml.kernel.org/r/20210705103229.8505-3-yee.lee@mediatek.comSigned-off-by:
Yee Lee <yee.lee@mediatek.com> Suggested-by:
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Marco Elver authored
Move the helper to check slub_debug_enabled, so that we can confine the use of #ifdef outside slub.c as well. Link: https://lkml.kernel.org/r/20210705103229.8505-2-yee.lee@mediatek.comSigned-off-by:
Matthew Wilcox <willy@infradead.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Chinwen Chang <chinwen.chang@mediatek.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com> Cc: Nicholas Tang <nicholas.tang@mediatek.com> Signed-off-by:
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Vitaly Kuznetsov authored
Two additional tests are added: - SMM triggered from L2 does not currupt L1 host state. - Save/restore during SMM triggered from L2 does not corrupt guest/host state. Signed-off-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20210628104425.391276-7-vkuznets@redhat.com> Reviewed-by:
Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Vitaly Kuznetsov authored
If the VM was migrated while in SMM, no nested state was saved/restored, and therefore svm_leave_smm has to load both save and control area of the vmcb12. Save area is already loaded from HSAVE area, so now load the control area as well from the vmcb12. Signed-off-by:
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Vitaly Kuznetsov authored
VMCB split commit 4995a368 ("KVM: SVM: Use a separate vmcb for the nested L2 guest") broke return from SMM when we entered there from guest (L2) mode. Gen2 WS2016/Hyper-V is known to do this on boot. The problem manifests itself like this: kvm_exit: reason EXIT_RSM rip 0x7ffbb280 info 0 0 kvm_emulate_insn: 0:7ffbb280: 0f aa kvm_smm_transition: vcpu 0: leaving SMM, smbase 0x7ffb3000 kvm_nested_vmrun: rip: 0x000000007ffbb280 vmcb: 0x0000000008224000 nrip: 0xffffffffffbbe119 int_ctl: 0x01020000 event_inj: 0x00000000 npt: on kvm_nested_intercepts: cr_read: 0000 cr_write: 0010 excp: 40060002 intercepts: fd44bfeb 0000217f 00000000 kvm_entry: vcpu 0, rip 0xffffffffffbbe119 kvm_exit: reason EXIT_NPF rip 0xffffffffffbbe119 info 200000006 1ab000 kvm_nested_vmexit: vcpu 0 reason npf rip 0xffffffffffbbe119 info1 0x0000000200000006 info2 0x00000000001ab000 intr_info 0x00000000 error_code 0x00000000 kvm_page_fault: address 1ab000 error_code 6 kvm_nested_vmexit_inject: reason EXIT_NPF info1 200000006 info2 1ab000 int_info 0 int_info_err 0 kvm_entry: vcpu 0, rip 0x7ffbb280 kvm_exit: reason EXIT_EXCP_GP rip 0x7ffbb280 info 0 0 kvm_emulate_insn: 0:7ffbb280: 0f aa kvm_inj_exception: #GP (0x0) Note: return to L2 succeeded but upon first exit to L1 its RIP points to 'RSM' instruction but we're not in SMM. The problem appears to be that VMCB01 gets irreversibly destroyed during SMM execution. Previously, we used to have 'hsave' VMCB where regular (pre-SMM) L1's state was saved upon nested_svm_vmexit() but now we just switch to VMCB01 from VMCB02. Pre-split (working) flow looked like: - SMM is triggered during L2's execution - L2's state is pushed to SMRAM - nested_svm_vmexit() restores L1's state from 'hsave' - SMM -> RSM - enter_svm_guest_mode() switches to L2 but keeps 'hsave' intact so we have pre-SMM (and pre L2 VMRUN) L1's state there - L2's state is restored from SMRAM - upon first exit L1's state is restored from L1. This was always broken with regards to svm_get_nested_state()/ svm_set_nested_state(): 'hsave' was never a part of what's being save and restored so migration happening during SMM triggered from L2 would never restore L1's state correctly. Post-split flow (broken) looks like: - SMM is triggered during L2's execution - L2's state is pushed to SMRAM - nested_svm_vmexit() switches to VMCB01 from VMCB02 - SMM -> RSM - enter_svm_guest_mode() switches from VMCB01 to VMCB02 but pre-SMM VMCB01 is already lost. - L2's state is restored from SMRAM - upon first exit L1's state is restored from VMCB01 but it is corrupted (reflects the state during 'RSM' execution). VMX doesn't have this problem because unlike VMCB, VMCS keeps both guest and host state so when we switch back to VMCS02 L1's state is intact there. To resolve the issue we need to save L1's state somewhere. We could've created a third VMCB for SMM but that would require us to modify saved state format. L1's architectural HSAVE area (pointed by MSR_VM_HSAVE_PA) seems appropriate: L0 is free to save any (or none) of L1's state there. Currently, KVM does 'none'. Note, for nested state migration to succeed, both source and destination hypervisors must have the fix. We, however, don't need to create a new flag indicating the fact that HSAVE area is now populated as migration during SMM triggered from L2 was always broken. Fixes: 4995a368 ("KVM: SVM: Use a separate vmcb for the nested L2 guest") Signed-off-by:
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Vitaly Kuznetsov authored
Separate the code setting non-VMLOAD-VMSAVE state from svm_set_nested_state() into its own function. This is going to be re-used from svm_enter_smm()/svm_leave_smm(). Signed-off-by:
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Vitaly Kuznetsov authored
APM states that "The address written to the VM_HSAVE_PA MSR, which holds the address of the page used to save the host state on a VMRUN, must point to a hypervisor-owned page. If this check fails, the WRMSR will fail with a #GP(0) exception. Note that a value of 0 is not considered valid for the VM_HSAVE_PA MSR and a VMRUN that is attempted while the HSAVE_PA is 0 will fail with a #GP(0) exception." svm_set_msr() already checks that the supplied address is valid, so only check for '0' is missing. Add it to nested_svm_vmrun(). Signed-off-by:
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Vitaly Kuznetsov authored
APM states that #GP is raised upon write to MSR_VM_HSAVE_PA when the supplied address is not page-aligned or is outside of "maximum supported physical address for this implementation". page_address_valid() check seems suitable. Also, forcefully page-align the address when it's written from VMM. Signed-off-by:
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Sean Christopherson authored
Use IS_ERR() instead of checking for a NULL pointer when querying for sev_pin_memory() failures. sev_pin_memory() always returns an error code cast to a pointer, or a valid pointer; it never returns NULL. Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Cc: Steve Rutherford <srutherford@google.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Ashish Kalra <ashish.kalra@amd.com> Fixes: d3d1af85 ("KVM: SVM: Add KVM_SEND_UPDATE_DATA command") Fixes: 15fb7de1 ("KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command") Signed-off-by:
Sean Christopherson <seanjc@google.com> Message-Id: <20210506175826.2166383-3-seanjc@google.com> Signed-off-by:
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Sean Christopherson authored
Return -EFAULT if copy_to_user() fails; if accessing user memory faults, copy_to_user() returns the number of bytes remaining, not an error code. Reported-by:
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Maxim Levitsky authored
In theory there are no side effects of not intercepting #SMI, because then #SMI becomes transparent to the OS and the KVM. Plus an observation on recent Zen2 CPUs reveals that these CPUs ignore #SMI interception and never deliver #SMI VMexits. This is also useful to test nested KVM to see that L1 handles #SMIs correctly in case when L1 doesn't intercept #SMI. Finally the default remains the same, the SMI are intercepted by default thus this patch doesn't have any effect unless non default module param value is used. Signed-off-by:
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Maxim Levitsky authored
Kernel never sends real INIT even to CPUs, other than on boot. Thus INIT interception is an error which should be caught by a check for an unknown VMexit reason. On top of that, the current INIT VM exit handler skips the current instruction which is wrong. That was added in commit 5ff3a351 ("KVM: x86: Move trivial instruction-based exit handlers to common code"). Fixes: 5ff3a351 ("KVM: x86: Move trivial instruction-based exit handlers to common code") Signed-off-by:
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