February 2025 - Linux-stable-mirror

[PATCH v3 3/5] misc: pci_endpoint_test: Fix irq_type to convey the correct type

by Kunihiko Hayashi

There are two variables that indicate the interrupt type to be used in the next test execution, "irq_type" as global and test->irq_type. The global is referenced from pci_endpoint_test_get_irq() to preserve the current type for ioctl(PCITEST_GET_IRQTYPE). The type set in this function isn't reflected in the global "irq_type", so ioctl(PCITEST_GET_IRQTYPE) returns the previous type. As a result, the wrong type will be displayed in "pcitest" as follows: # pcitest -i 0 SET IRQ TYPE TO LEGACY: OKAY # pcitest -I GET IRQ TYPE: MSI Fix this issue by propagating the current type to the global "irq_type". Cc: stable(a)vger.kernel.org Fixes: b2ba9225e031 ("misc: pci_endpoint_test: Avoid using module parameter to determine irqtype") Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko(a)socionext.com> --- drivers/misc/pci_endpoint_test.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/misc/pci_endpoint_test.c b/drivers/misc/pci_endpoint_test.c index f13fa32ef91a..6a0972e7674f 100644 --- a/drivers/misc/pci_endpoint_test.c +++ b/drivers/misc/pci_endpoint_test.c @@ -829,6 +829,7 @@ static int pci_endpoint_test_set_irq(struct pci_endpoint_test *test, return ret; } + irq_type = test->irq_type; return 0; } -- 2.25.1

2 weeks

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[PATCH v3] KVM: PPC: Enable CAP_SPAPR_TCE_VFIO on pSeries KVM guests

by Amit Machhiwal

Currently on book3s-hv, the capability KVM_CAP_SPAPR_TCE_VFIO is only available for KVM Guests running on PowerNV and not for the KVM guests running on pSeries hypervisors. This prevents a pSeries L2 guest from leveraging the in-kernel acceleration for H_PUT_TCE_INDIRECT and H_STUFF_TCE hcalls that results in slow startup times for large memory guests. Support for VFIO on pSeries was restored in commit f431a8cde7f1 ("powerpc/iommu: Reimplement the iommu_table_group_ops for pSeries"), making it possible to re-enable this capability on pSeries hosts. This change enables KVM_CAP_SPAPR_TCE_VFIO for nested PAPR guests on pSeries, while maintaining the existing behavior on PowerNV. Booting an L2 guest with 128GB of memory shows an average 11% improvement in startup time. Fixes: f431a8cde7f1 ("powerpc/iommu: Reimplement the iommu_table_group_ops for pSeries") Cc: stable(a)vger.kernel.org Reviewed-by: Vaibhav Jain <vaibhav(a)linux.ibm.com> Reviewed-by: Ritesh Harjani (IBM) <ritesh.list(a)gmail.com> Signed-off-by: Amit Machhiwal <amachhiw(a)linux.ibm.com> --- Changes since v2: * Updated the patch description * v2: https://lore.kernel.org/all/20250129094033.2265211-1-amachhiw@linux.ibm.com/ Changes since v1: * Addressed review comments from Ritesh * v1: https://lore.kernel.org/all/20250109132053.158436-1-amachhiw@linux.ibm.com/ arch/powerpc/kvm/powerpc.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index ce1d91eed231..a7138eb18d59 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -543,26 +543,23 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) r = !hv_enabled; break; #ifdef CONFIG_KVM_MPIC case KVM_CAP_IRQ_MPIC: r = 1; break; #endif #ifdef CONFIG_PPC_BOOK3S_64 case KVM_CAP_SPAPR_TCE: + fallthrough; case KVM_CAP_SPAPR_TCE_64: - r = 1; - break; case KVM_CAP_SPAPR_TCE_VFIO: - r = !!cpu_has_feature(CPU_FTR_HVMODE); - break; case KVM_CAP_PPC_RTAS: case KVM_CAP_PPC_FIXUP_HCALL: case KVM_CAP_PPC_ENABLE_HCALL: #ifdef CONFIG_KVM_XICS case KVM_CAP_IRQ_XICS: #endif case KVM_CAP_PPC_GET_CPU_CHAR: r = 1; break; #ifdef CONFIG_KVM_XIVE base-commit: 6537cfb395f352782918d8ee7b7f10ba2cc3cbf2 -- 2.48.1

2 weeks

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[PATCH v2 2/5] ftrace: Do not add duplicate entries in subops manager ops

by Steven Rostedt

From: Steven Rostedt <rostedt(a)goodmis.org> Check if a function is already in the manager ops of a subops. A manager ops contains multiple subops, and if two or more subops are tracing the same function, the manager ops only needs a single entry in its hash. Cc: stable(a)vger.kernel.org Fixes: 4f554e955614f ("ftrace: Add ftrace_set_filter_ips function") Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- kernel/trace/ftrace.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 03b35a05808c..189eb0a12f4b 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5717,6 +5717,9 @@ __ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove) return -ENOENT; free_hash_entry(hash, entry); return 0; + } else if (__ftrace_lookup_ip(hash, ip) != NULL) { + /* Already exists */ + return 0; } entry = add_hash_entry(hash, ip); -- 2.47.2

2 weeks

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[PATCH] drivers: loongson: Add check for devm_kstrdup()

by Haoxiang Li

Add check for the return value of devm_kstrdup() in loongson2_guts_probe() to catch potential exception. Fixes: b82621ac8450 ("soc: loongson: add GUTS driver for loongson-2 platforms") Cc: stable(a)vger.kernel.org Signed-off-by: Haoxiang Li <haoxiang_li2024(a)163.com> --- drivers/soc/loongson/loongson2_guts.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/soc/loongson/loongson2_guts.c b/drivers/soc/loongson/loongson2_guts.c index ae42e3a9127f..26212cfcf6b0 100644 --- a/drivers/soc/loongson/loongson2_guts.c +++ b/drivers/soc/loongson/loongson2_guts.c @@ -117,6 +117,8 @@ static int loongson2_guts_probe(struct platform_device *pdev) if (machine) soc_dev_attr.machine = devm_kstrdup(dev, machine, GFP_KERNEL); + if (!soc_dev_attr.machine) + return -ENOMEM; svr = loongson2_guts_get_svr(); soc_die = loongson2_soc_die_match(svr, loongson2_soc_die); if (soc_die) { -- 2.25.1

2 weeks

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[PATCH] smb: client: Add check for next_buffer in receive_encrypted_standard()

by Haoxiang Li

Add check for the return value of cifs_buf_get() and cifs_small_buf_get() in receive_encrypted_standard() to prevent null pointer dereference. Fixes: eec04ea11969 ("smb: client: fix OOB in receive_encrypted_standard()") Cc: stable(a)vger.kernel.org Signed-off-by: Haoxiang Li <haoxiang_li2024(a)163.com> --- fs/smb/client/smb2ops.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c index ec36bed54b0b..2ca8fe196051 100644 --- a/fs/smb/client/smb2ops.c +++ b/fs/smb/client/smb2ops.c @@ -4964,6 +4964,10 @@ receive_encrypted_standard(struct TCP_Server_Info *server, next_buffer = (char *)cifs_buf_get(); else next_buffer = (char *)cifs_small_buf_get(); + if (!next_buffer) { + cifs_server_dbg(VFS, "No memory for (large) SMB response\n"); + return -1; + } memcpy(next_buffer, buf + next_cmd, pdu_length - next_cmd); } -- 2.25.1

2 weeks

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[PATCH v2 4/5] fprobe: Fix accounting of when to unregister from function graph

by Steven Rostedt

From: Steven Rostedt <rostedt(a)goodmis.org> When adding a new fprobe, it will update the function hash to the functions the fprobe is attached to and register with function graph to have it call the registered functions. The fprobe_graph_active variable keeps track of the number of fprobes that are using function graph. If two fprobes attach to the same function, it increments the fprobe_graph_active for each of them. But when they are removed, the first fprobe to be removed will see that the function it is attached to is also used by another fprobe and it will not remove that function from function_graph. The logic will skip decrementing the fprobe_graph_active variable. This causes the fprobe_graph_active variable to not go to zero when all fprobes are removed, and in doing so it does not unregister from function graph. As the fgraph ops hash will now be empty, and an empty filter hash means all functions are enabled, this triggers function graph to add a callback to the fprobe infrastructure for every function! # echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events # echo "f:myevent2 kernel_clone%return" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc0024000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # > /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions trace_initcall_start_cb (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 try_to_run_init_process (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 x86_pmu_show_pmu_cap (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 cleanup_rapl_pmus (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_free_pcibus_map (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_types_exit (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 uncore_pci_exit.part.0 (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 kvm_shutdown (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 vmx_dump_msrs (1) tramp: 0xffffffffc0026000 (function_trace_call+0x0/0x170) ->function_trace_call+0x0/0x170 [..] # cat /sys/kernel/tracing/enabled_functions | wc -l 54702 If a fprobe is being removed and all its functions are also traced by other fprobes, still decrement the fprobe_graph_active counter. Cc: stable(a)vger.kernel.org Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer") Closes: https://lore.kernel.org/all/20250217114918.10397-A-hca@linux.ibm.com/ Reported-by: Heiko Carstens <hca(a)linux.ibm.com> Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- Changes since v1: https://lore.kernel.org/20250218193126.619197190@goodmis.org - Move the check into fprobe_graph_remove_ips() to keep it matching with fprobe_graph_add_ips() (Masami Hiramatsu) kernel/trace/fprobe.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 62e8f7d56602..33082c4e8154 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -407,7 +407,8 @@ static void fprobe_graph_remove_ips(unsigned long *addrs, int num) if (!fprobe_graph_active) unregister_ftrace_graph(&fprobe_graph_ops); - ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0); + if (num) + ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0); } static int symbols_cmp(const void *a, const void *b) @@ -677,8 +678,7 @@ int unregister_fprobe(struct fprobe *fp) } del_fprobe_hash(fp); - if (count) - fprobe_graph_remove_ips(addrs, count); + fprobe_graph_remove_ips(addrs, count); kfree_rcu(hlist_array, rcu); fp->hlist_array = NULL; -- 2.47.2

2 weeks

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[PATCH v2 3/5] fprobe: Always unregister fgraph function from ops

by Steven Rostedt

From: Steven Rostedt <rostedt(a)goodmis.org> When the last fprobe is removed, it calls unregister_ftrace_graph() to remove the graph_ops from function graph. The issue is when it does so, it calls return before removing the function from its graph ops via ftrace_set_filter_ips(). This leaves the last function lingering in the fprobe's fgraph ops and if a probe is added it also enables that last function (even though the callback will just drop it, it does add unneeded overhead to make that call). # echo "f:myevent1 kernel_clone" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # echo "f:myevent2 schedule_timeout" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kernel_clone (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 schedule_timeout (1) tramp: 0xffffffffc02f3000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 # > /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions # echo "f:myevent3 kmem_cache_free" >> /sys/kernel/tracing/dynamic_events # cat /sys/kernel/tracing/enabled_functions kmem_cache_free (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 schedule_timeout (1) tramp: 0xffffffffc0219000 (ftrace_graph_func+0x0/0x60) ->ftrace_graph_func+0x0/0x60 The above enabled a fprobe on kernel_clone, and then on schedule_timeout. The content of the enabled_functions shows the functions that have a callback attached to them. The fprobe attached to those functions properly. Then the fprobes were cleared, and enabled_functions was empty after that. But after adding a fprobe on kmem_cache_free, the enabled_functions shows that the schedule_timeout was attached again. This is because it was still left in the fprobe ops that is used to tell function graph what functions it wants callbacks from. Cc: stable(a)vger.kernel.org Fixes: 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer") Signed-off-by: Steven Rostedt (Google) <rostedt(a)goodmis.org> --- kernel/trace/fprobe.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 2560b312ad57..62e8f7d56602 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -403,11 +403,9 @@ static void fprobe_graph_remove_ips(unsigned long *addrs, int num) lockdep_assert_held(&fprobe_mutex); fprobe_graph_active--; - if (!fprobe_graph_active) { - /* Q: should we unregister it ? */ + /* Q: should we unregister it ? */ + if (!fprobe_graph_active) unregister_ftrace_graph(&fprobe_graph_ops); - return; - } ftrace_set_filter_ips(&fprobe_graph_ops.ops, addrs, num, 1, 0); } -- 2.47.2

2 weeks

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[PATCH v3] arm: pgtable: fix NULL pointer dereference issue

by Qi Zheng

When update_mmu_cache_range() is called by update_mmu_cache(), the vmf parameter is NULL, which will cause a NULL pointer dereference issue in adjust_pte(): Unable to handle kernel NULL pointer dereference at virtual address 00000030 when read Hardware name: Atmel AT91SAM9 PC is at update_mmu_cache_range+0x1e0/0x278 LR is at pte_offset_map_rw_nolock+0x18/0x2c Call trace: update_mmu_cache_range from remove_migration_pte+0x29c/0x2ec remove_migration_pte from rmap_walk_file+0xcc/0x130 rmap_walk_file from remove_migration_ptes+0x90/0xa4 remove_migration_ptes from migrate_pages_batch+0x6d4/0x858 migrate_pages_batch from migrate_pages+0x188/0x488 migrate_pages from compact_zone+0x56c/0x954 compact_zone from compact_node+0x90/0xf0 compact_node from kcompactd+0x1d4/0x204 kcompactd from kthread+0x120/0x12c kthread from ret_from_fork+0x14/0x38 Exception stack(0xc0d8bfb0 to 0xc0d8bff8) To fix it, do not rely on whether 'ptl' is equal to decide whether to hold the pte lock, but decide it by whether CONFIG_SPLIT_PTE_PTLOCKS is enabled. In addition, if two vmas map to the same PTE page, there is no need to hold the pte lock again, otherwise a deadlock will occur. Just add the need_lock parameter to let adjust_pte() know this information. Reported-by: Ezra Buehler <ezra.buehler(a)husqvarnagroup.com> Closes: https://lore.kernel.org/lkml/CAM1KZSmZ2T_riHvay+7cKEFxoPgeVpHkVFTzVVEQ1BO0c… Fixes: fc9c45b71f43 ("arm: adjust_pte() use pte_offset_map_rw_nolock()") Cc: stable(a)vger.kernel.org Signed-off-by: Qi Zheng <zhengqi.arch(a)bytedance.com> Acked-by: David Hildenbrand <david(a)redhat.com> --- Changes in v3: - move pmd_start_addr and pmd_end_addr to the top and initialize directly (David Hildenbrand) - collect an Acked-by Changes in v2: - change Ezra's email address (Ezra Buehler) - some cleanups (David Hildenbrand) arch/arm/mm/fault-armv.c | 37 +++++++++++++++++++++++++------------ 1 file changed, 25 insertions(+), 12 deletions(-) diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c index 2bec87c3327d2..39fd5df733178 100644 --- a/arch/arm/mm/fault-armv.c +++ b/arch/arm/mm/fault-armv.c @@ -62,7 +62,7 @@ static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address, } static int adjust_pte(struct vm_area_struct *vma, unsigned long address, - unsigned long pfn, struct vm_fault *vmf) + unsigned long pfn, bool need_lock) { spinlock_t *ptl; pgd_t *pgd; @@ -99,12 +99,11 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address, if (!pte) return 0; - /* - * If we are using split PTE locks, then we need to take the page - * lock here. Otherwise we are using shared mm->page_table_lock - * which is already locked, thus cannot take it. - */ - if (ptl != vmf->ptl) { + if (need_lock) { + /* + * Use nested version here to indicate that we are already + * holding one similar spinlock. + */ spin_lock_nested(ptl, SINGLE_DEPTH_NESTING); if (unlikely(!pmd_same(pmdval, pmdp_get_lockless(pmd)))) { pte_unmap_unlock(pte, ptl); @@ -114,7 +113,7 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address, ret = do_adjust_pte(vma, address, pfn, pte); - if (ptl != vmf->ptl) + if (need_lock) spin_unlock(ptl); pte_unmap(pte); @@ -123,9 +122,10 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address, static void make_coherent(struct address_space *mapping, struct vm_area_struct *vma, - unsigned long addr, pte_t *ptep, unsigned long pfn, - struct vm_fault *vmf) + unsigned long addr, pte_t *ptep, unsigned long pfn) { + const unsigned long pmd_start_addr = ALIGN_DOWN(addr, PMD_SIZE); + const unsigned long pmd_end_addr = pmd_start_addr + PMD_SIZE; struct mm_struct *mm = vma->vm_mm; struct vm_area_struct *mpnt; unsigned long offset; @@ -141,6 +141,14 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma, */ flush_dcache_mmap_lock(mapping); vma_interval_tree_foreach(mpnt, &mapping->i_mmap, pgoff, pgoff) { + /* + * If we are using split PTE locks, then we need to take the pte + * lock. Otherwise we are using shared mm->page_table_lock which + * is already locked, thus cannot take it. + */ + bool need_lock = IS_ENABLED(CONFIG_SPLIT_PTE_PTLOCKS); + unsigned long mpnt_addr; + /* * If this VMA is not in our MM, we can ignore it. * Note that we intentionally mask out the VMA @@ -151,7 +159,12 @@ make_coherent(struct address_space *mapping, struct vm_area_struct *vma, if (!(mpnt->vm_flags & VM_MAYSHARE)) continue; offset = (pgoff - mpnt->vm_pgoff) << PAGE_SHIFT; - aliases += adjust_pte(mpnt, mpnt->vm_start + offset, pfn, vmf); + mpnt_addr = mpnt->vm_start + offset; + + /* Avoid deadlocks by not grabbing the same PTE lock again. */ + if (mpnt_addr >= pmd_start_addr && mpnt_addr < pmd_end_addr) + need_lock = false; + aliases += adjust_pte(mpnt, mpnt_addr, pfn, need_lock); } flush_dcache_mmap_unlock(mapping); if (aliases) @@ -194,7 +207,7 @@ void update_mmu_cache_range(struct vm_fault *vmf, struct vm_area_struct *vma, __flush_dcache_folio(mapping, folio); if (mapping) { if (cache_is_vivt()) - make_coherent(mapping, vma, addr, ptep, pfn, vmf); + make_coherent(mapping, vma, addr, ptep, pfn); else if (vma->vm_flags & VM_EXEC) __flush_icache_all(); } -- 2.20.1

2 weeks

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+ mm-hugetlb-wait-for-hugetlb-folios-to-be-freed.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm/hugetlb: wait for hugetlb folios to be freed has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-hugetlb-wait-for-hugetlb-folios-to-be-freed.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Ge Yang <yangge1116(a)126.com> Subject: mm/hugetlb: wait for hugetlb folios to be freed Date: Wed, 19 Feb 2025 11:46:44 +0800 Since the introduction of commit c77c0a8ac4c52 ("mm/hugetlb: defer freeing of huge pages if in non-task context"), which supports deferring the freeing of hugetlb pages, the allocation of contiguous memory through cma_alloc() may fail probabilistically. In the CMA allocation process, if it is found that the CMA area is occupied by in-use hugetlb folios, these in-use hugetlb folios need to be migrated to another location. When there are no available hugetlb folios in the free hugetlb pool during the migration of in-use hugetlb folios, new folios are allocated from the buddy system. A temporary state is set on the newly allocated folio. Upon completion of the hugetlb folio migration, the temporary state is transferred from the new folios to the old folios. Normally, when the old folios with the temporary state are freed, it is directly released back to the buddy system. However, due to the deferred freeing of hugetlb pages, the PageBuddy() check fails, ultimately leading to the failure of cma_alloc(). Here is a simplified call trace illustrating the process: cma_alloc() ->__alloc_contig_migrate_range() // Migrate in-use hugetlb folios ->unmap_and_move_huge_page() ->folio_putback_hugetlb() // Free old folios ->test_pages_isolated() ->__test_page_isolated_in_pageblock() ->PageBuddy(page) // Check if the page is in buddy To resolve this issue, we have implemented a function named wait_for_freed_hugetlb_folios(). This function ensures that the hugetlb folios are properly released back to the buddy system after their migration is completed. By invoking wait_for_freed_hugetlb_folios() before calling PageBuddy(), we ensure that PageBuddy() will succeed. Link: https://lkml.kernel.org/r/1739936804-18199-1-git-send-email-yangge1116@126.… Fixes: c77c0a8ac4c52 ("mm/hugetlb: defer freeing of huge pages if in non-task context") Signed-off-by: Ge Yang <yangge1116(a)126.com> Reviewed-by: Muchun Song <muchun.song(a)linux.dev> Acked-by: David Hildenbrand <david(a)redhat.com> Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com> Cc: Barry Song <21cnbao(a)gmail.com> Cc: Oscar Salvador <osalvador(a)suse.de> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- include/linux/hugetlb.h | 5 +++++ mm/hugetlb.c | 8 ++++++++ mm/page_isolation.c | 10 ++++++++++ 3 files changed, 23 insertions(+) --- a/include/linux/hugetlb.h~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed +++ a/include/linux/hugetlb.h @@ -682,6 +682,7 @@ struct huge_bootmem_page { int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list); int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn); +void wait_for_freed_hugetlb_folios(void); struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, unsigned long addr, bool cow_from_owner); struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid, @@ -1066,6 +1067,10 @@ static inline int replace_free_hugepage_ return 0; } +static inline void wait_for_freed_hugetlb_folios(void) +{ +} + static inline struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma, unsigned long addr, bool cow_from_owner) --- a/mm/hugetlb.c~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed +++ a/mm/hugetlb.c @@ -2943,6 +2943,14 @@ int replace_free_hugepage_folios(unsigne return ret; } +void wait_for_freed_hugetlb_folios(void) +{ + if (llist_empty(&hpage_freelist)) + return; + + flush_work(&free_hpage_work); +} + typedef enum { /* * For either 0/1: we checked the per-vma resv map, and one resv --- a/mm/page_isolation.c~mm-hugetlb-wait-for-hugetlb-folios-to-be-freed +++ a/mm/page_isolation.c @@ -608,6 +608,16 @@ int test_pages_isolated(unsigned long st int ret; /* + * Due to the deferred freeing of hugetlb folios, the hugepage folios may + * not immediately release to the buddy system. This can cause PageBuddy() + * to fail in __test_page_isolated_in_pageblock(). To ensure that the + * hugetlb folios are properly released back to the buddy system, we + * invoke the wait_for_freed_hugetlb_folios() function to wait for the + * release to complete. + */ + wait_for_freed_hugetlb_folios(); + + /* * Note: pageblock_nr_pages != MAX_PAGE_ORDER. Then, chunks of free * pages are not aligned to pageblock_nr_pages. * Then we just check migratetype first. _ Patches currently in -mm which might be from yangge1116(a)126.com are mm-hugetlb-wait-for-hugetlb-folios-to-be-freed.patch

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[PATCH v2] jfs: fix slab-out-of-bounds read in ea_get()

by Qasim Ijaz

During the "size_check" label in ea_get(), the code checks if the extended attribute list (xattr) size matches ea_size. If not, it logs "ea_get: invalid extended attribute" and calls print_hex_dump(). Here, EALIST_SIZE(ea_buf->xattr) returns 4110417968, which exceeds INT_MAX (2,147,483,647). Then ea_size is clamped: int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr)); Although clamp_t aims to bound ea_size between 0 and 4110417968, the upper limit is treated as an int, causing an overflow above 2^31 - 1. This leads "size" to wrap around and become negative (-184549328). The "size" is then passed to print_hex_dump() (called "len" in print_hex_dump()), it is passed as type size_t (an unsigned type), this is then stored inside a variable called "int remaining", which is then assigned to "int linelen" which is then passed to hex_dump_to_buffer(). In print_hex_dump() the for loop, iterates through 0 to len-1, where len is 18446744073525002176, calling hex_dump_to_buffer() on each iteration: for (i = 0; i < len; i += rowsize) { linelen = min(remaining, rowsize); remaining -= rowsize; hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, linebuf, sizeof(linebuf), ascii); ... } The expected stopping condition (i < len) is effectively broken since len is corrupted and very large. This eventually leads to the "ptr+i" being passed to hex_dump_to_buffer() to get closer to the end of the actual bounds of "ptr", eventually an out of bounds access is done in hex_dump_to_buffer() in the following for loop: for (j = 0; j < len; j++) { if (linebuflen < lx + 2) goto overflow2; ch = ptr[j]; ... } To fix this we should validate "EALIST_SIZE(ea_buf->xattr)" before it is utilised. Reported-by: syzbot <syzbot+4e6e7e4279d046613bc5(a)syzkaller.appspotmail.com> Tested-by: syzbot <syzbot+4e6e7e4279d046613bc5(a)syzkaller.appspotmail.com> Closes: https://syzkaller.appspot.com/bug?extid=4e6e7e4279d046613bc5 Fixes: d9f9d96136cb ("jfs: xattr: check invalid xattr size more strictly") Cc: stable(a)vger.kernel.org Signed-off-by: Qasim Ijaz <qasdev00(a)gmail.com> --- v2: - Added Cc stable tag fs/jfs/xattr.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c index 24afbae87225..7575c51cce9b 100644 --- a/fs/jfs/xattr.c +++ b/fs/jfs/xattr.c @@ -559,11 +555,16 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) size_check: if (EALIST_SIZE(ea_buf->xattr) != ea_size) { - int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr)); - - printk(KERN_ERR "ea_get: invalid extended attribute\n"); - print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, - ea_buf->xattr, size, 1); + if (unlikely(EALIST_SIZE(ea_buf->xattr) > INT_MAX)) { + printk(KERN_ERR "ea_get: extended attribute size too large: %u > INT_MAX\n", + EALIST_SIZE(ea_buf->xattr)); + } else { + int size = clamp_t(int, ea_size, 0, EALIST_SIZE(ea_buf->xattr)); + + printk(KERN_ERR "ea_get: invalid extended attribute\n"); + print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, + ea_buf->xattr, size, 1); + } ea_release(inode, ea_buf); rc = -EIO; goto clean_up; -- 2.39.5

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Linux-stable-mirror February 2025