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[STABLE 5.15.y] [PATCH] KVM: arm64: Fix softirq masking in FPSIMD register saving sequence

by Will Deacon

Stable commit 23249dade24e ("KVM: arm64: Fix kernel BUG() due to bad backport of FPSIMD/SVE/SME fix") fixed a kernel BUG() caused by a bad backport of upstream commit fbc7e61195e2 ("KVM: arm64: Unconditionally save+flush host FPSIMD/SVE/SME state") by ensuring that softirqs are disabled/enabled across the fpsimd register save operation. Unfortunately, although this fixes the original issue, it can now lead to deadlock when re-enabling softirqs causes pending softirqs to be handled with locks already held: | BUG: spinlock recursion on CPU#7, CPU 3/KVM/57616 | lock: 0xffff3045ef850240, .magic: dead4ead, .owner: CPU 3/KVM/57616, .owner_cpu: 7 | CPU: 7 PID: 57616 Comm: CPU 3/KVM Tainted: G O 6.1.152 #1 | Hardware name: SoftIron SoftIron Platform Mainboard/SoftIron Platform Mainboard, BIOS 1.31 May 11 2023 | Call trace: | dump_backtrace+0xe4/0x110 | show_stack+0x20/0x30 | dump_stack_lvl+0x6c/0x88 | dump_stack+0x18/0x34 | spin_dump+0x98/0xac | do_raw_spin_lock+0x70/0x128 | _raw_spin_lock+0x18/0x28 | raw_spin_rq_lock_nested+0x18/0x28 | update_blocked_averages+0x70/0x550 | run_rebalance_domains+0x50/0x70 | handle_softirqs+0x198/0x328 | __do_softirq+0x1c/0x28 | ____do_softirq+0x18/0x28 | call_on_irq_stack+0x30/0x48 | do_softirq_own_stack+0x24/0x30 | do_softirq+0x74/0x90 | __local_bh_enable_ip+0x64/0x80 | fpsimd_save_and_flush_cpu_state+0x5c/0x68 | kvm_arch_vcpu_put_fp+0x4c/0x88 | kvm_arch_vcpu_put+0x28/0x88 | kvm_sched_out+0x38/0x58 | __schedule+0x55c/0x6c8 | schedule+0x60/0xa8 Take a tiny step towards the upstream fix in 9b19700e623f ("arm64: fpsimd: Drop unneeded 'busy' flag") by additionally disabling hardirqs while saving the fpsimd registers. Cc: Ard Biesheuvel <ardb(a)kernel.org> Cc: Lee Jones <lee(a)kernel.org> Cc: Sasha Levin <sashal(a)kernel.org> Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org Cc: <stable(a)vger.kernel.org> # 5.15.y Fixes: 23249dade24e ("KVM: arm64: Fix kernel BUG() due to bad backport of FPSIMD/SVE/SME fix") Reported-by: Kenneth Van Alstyne <kvanals(a)kvanals.org> Link: https://lore.kernel.org/r/010001999bae0958-4d80d25d-8dda-4006-a6b9-798f3e77… Signed-off-by: Will Deacon <will(a)kernel.org> --- arch/arm64/kernel/fpsimd.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index fc51cdd5aaa7..db1ed940a6dc 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1300,13 +1300,17 @@ static void fpsimd_flush_cpu_state(void) */ void fpsimd_save_and_flush_cpu_state(void) { + unsigned long flags; + if (!system_supports_fpsimd()) return; WARN_ON(preemptible()); - get_cpu_fpsimd_context(); + local_irq_save(flags); + __get_cpu_fpsimd_context(); fpsimd_save(); fpsimd_flush_cpu_state(); - put_cpu_fpsimd_context(); + __put_cpu_fpsimd_context(); + local_irq_restore(flags); } #ifdef CONFIG_KERNEL_MODE_NEON -- 2.51.0.618.g983fd99d29-goog

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Linux 6.17.1

by Greg Kroah-Hartman

I'm announcing the release of the 6.17.1 kernel. All users of the 6.17 kernel series must upgrade. The updated 6.17.y git tree can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-6.17.y and can be browsed at the normal kernel.org git web browser: https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary thanks, greg k-h ------------ Makefile | 2 block/blk-mq-tag.c | 1 drivers/media/i2c/tc358743.c | 4 - drivers/media/pci/b2c2/flexcop-pci.c | 2 drivers/media/platform/qcom/iris/iris_buffer.c | 10 +++ drivers/media/platform/st/stm32/stm32-csi.c | 4 - drivers/media/rc/imon.c | 27 ++++++--- drivers/media/tuners/xc5000.c | 2 drivers/media/usb/uvc/uvc_driver.c | 73 +++++++++++++++---------- drivers/media/usb/uvc/uvcvideo.h | 2 drivers/net/wireless/ath/ath11k/qmi.c | 2 drivers/net/wireless/realtek/rtw89/core.c | 30 ++++++++-- drivers/net/wireless/realtek/rtw89/core.h | 35 +++++++++++ drivers/net/wireless/realtek/rtw89/pci.c | 3 - drivers/net/wireless/realtek/rtw89/ser.c | 2 drivers/target/target_core_configfs.c | 2 mm/swapfile.c | 3 + scripts/gcc-plugins/gcc-common.h | 7 ++ sound/soc/qcom/qdsp6/topology.c | 4 - sound/usb/midi.c | 9 +-- 20 files changed, 165 insertions(+), 59 deletions(-) Chandra Mohan Sundar (1): media: stm32-csi: Fix dereference before NULL check Charan Teja Kalla (1): mm: swap: check for stable address space before operating on the VMA Dikshita Agarwal (1): media: iris: Fix memory leak by freeing untracked persist buffer Duoming Zhou (3): media: b2c2: Fix use-after-free causing by irq_check_work in flexcop_pci_remove media: i2c: tc358743: Fix use-after-free bugs caused by orphan timer in probe media: tuner: xc5000: Fix use-after-free in xc5000_release Fedor Pchelkin (1): wifi: rtw89: fix use-after-free in rtw89_core_tx_kick_off_and_wait() Greg Kroah-Hartman (1): Linux 6.17.1 Jeongjun Park (1): ALSA: usb-audio: fix race condition to UAF in snd_usbmidi_free Kees Cook (1): gcc-plugins: Remove TODO_verify_il for GCC >= 16 Larshin Sergey (1): media: rc: fix races with imon_disconnect() Matvey Kovalev (1): wifi: ath11k: fix NULL dereference in ath11k_qmi_m3_load() Srinivas Kandagatla (1): ASoC: qcom: audioreach: fix potential null pointer dereference Thadeu Lima de Souza Cascardo (1): media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID Wang Haoran (1): scsi: target: target_core_configfs: Add length check to avoid buffer overflow Yu Kuai (1): blk-mq: fix blk_mq_tags double free while nr_requests grown

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Linux 6.16.11

by Greg Kroah-Hartman

I'm announcing the release of the 6.16.11 kernel. All users of the 6.16 kernel series must upgrade. The updated 6.16.y git tree can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-6.16.y and can be browsed at the normal kernel.org git web browser: https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary thanks, greg k-h ------------ Makefile | 2 block/blk-mq-tag.c | 1 drivers/media/i2c/tc358743.c | 4 - drivers/media/pci/b2c2/flexcop-pci.c | 2 drivers/media/platform/qcom/iris/iris_buffer.c | 10 +++ drivers/media/platform/st/stm32/stm32-csi.c | 4 - drivers/media/rc/imon.c | 27 ++++++--- drivers/media/tuners/xc5000.c | 2 drivers/media/usb/uvc/uvc_driver.c | 73 +++++++++++++++---------- drivers/media/usb/uvc/uvcvideo.h | 2 drivers/net/wireless/ath/ath11k/qmi.c | 2 drivers/target/target_core_configfs.c | 2 mm/swapfile.c | 3 + scripts/gcc-plugins/gcc-common.h | 7 ++ sound/soc/qcom/qdsp6/topology.c | 4 - sound/usb/midi.c | 9 +-- 16 files changed, 104 insertions(+), 50 deletions(-) Chandra Mohan Sundar (1): media: stm32-csi: Fix dereference before NULL check Charan Teja Kalla (1): mm: swap: check for stable address space before operating on the VMA Dikshita Agarwal (1): media: iris: Fix memory leak by freeing untracked persist buffer Duoming Zhou (3): media: b2c2: Fix use-after-free causing by irq_check_work in flexcop_pci_remove media: i2c: tc358743: Fix use-after-free bugs caused by orphan timer in probe media: tuner: xc5000: Fix use-after-free in xc5000_release Greg Kroah-Hartman (1): Linux 6.16.11 Jeongjun Park (1): ALSA: usb-audio: fix race condition to UAF in snd_usbmidi_free Kees Cook (1): gcc-plugins: Remove TODO_verify_il for GCC >= 16 Larshin Sergey (1): media: rc: fix races with imon_disconnect() Matvey Kovalev (1): wifi: ath11k: fix NULL dereference in ath11k_qmi_m3_load() Srinivas Kandagatla (1): ASoC: qcom: audioreach: fix potential null pointer dereference Thadeu Lima de Souza Cascardo (1): media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID Wang Haoran (1): scsi: target: target_core_configfs: Add length check to avoid buffer overflow Yu Kuai (1): blk-mq: fix blk_mq_tags double free while nr_requests grown

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Linux 6.12.51

by Greg Kroah-Hartman

I'm announcing the release of the 6.12.51 kernel. All users of the 6.12 kernel series must upgrade. The updated 6.12.y git tree can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-6.12.y and can be browsed at the normal kernel.org git web browser: https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary thanks, greg k-h ------------ Makefile | 2 drivers/media/pci/b2c2/flexcop-pci.c | 2 drivers/media/rc/imon.c | 27 +++++++++--- drivers/media/tuners/xc5000.c | 2 drivers/media/usb/uvc/uvc_driver.c | 73 +++++++++++++++++++++------------- drivers/media/usb/uvc/uvcvideo.h | 2 drivers/net/wireless/ath/ath11k/qmi.c | 2 drivers/target/target_core_configfs.c | 2 include/crypto/sha256_base.h | 2 mm/swapfile.c | 3 + scripts/gcc-plugins/gcc-common.h | 7 +++ sound/soc/qcom/qdsp6/topology.c | 4 - 12 files changed, 86 insertions(+), 42 deletions(-) Breno Leitao (1): crypto: sha256 - fix crash at kexec Charan Teja Kalla (1): mm: swap: check for stable address space before operating on the VMA Duoming Zhou (2): media: b2c2: Fix use-after-free causing by irq_check_work in flexcop_pci_remove media: tuner: xc5000: Fix use-after-free in xc5000_release Greg Kroah-Hartman (1): Linux 6.12.51 Kees Cook (1): gcc-plugins: Remove TODO_verify_il for GCC >= 16 Larshin Sergey (1): media: rc: fix races with imon_disconnect() Matvey Kovalev (1): wifi: ath11k: fix NULL dereference in ath11k_qmi_m3_load() Srinivas Kandagatla (1): ASoC: qcom: audioreach: fix potential null pointer dereference Thadeu Lima de Souza Cascardo (1): media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID Wang Haoran (1): scsi: target: target_core_configfs: Add length check to avoid buffer overflow

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Linux 6.6.110

by Greg Kroah-Hartman

I'm announcing the release of the 6.6.110 kernel. All users of the 6.6 kernel series must upgrade. The updated 6.6.y git tree can be found at: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-6.6.y and can be browsed at the normal kernel.org git web browser: https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary thanks, greg k-h ------------ Makefile | 2 drivers/media/pci/b2c2/flexcop-pci.c | 2 drivers/media/rc/imon.c | 27 +++++++++--- drivers/media/usb/uvc/uvc_driver.c | 73 +++++++++++++++++++++------------- drivers/media/usb/uvc/uvcvideo.h | 2 drivers/target/target_core_configfs.c | 2 include/crypto/sha256_base.h | 2 scripts/gcc-plugins/gcc-common.h | 7 +++ sound/soc/qcom/qdsp6/topology.c | 4 - 9 files changed, 81 insertions(+), 40 deletions(-) Breno Leitao (1): crypto: sha256 - fix crash at kexec Duoming Zhou (1): media: b2c2: Fix use-after-free causing by irq_check_work in flexcop_pci_remove Greg Kroah-Hartman (1): Linux 6.6.110 Kees Cook (1): gcc-plugins: Remove TODO_verify_il for GCC >= 16 Larshin Sergey (1): media: rc: fix races with imon_disconnect() Srinivas Kandagatla (1): ASoC: qcom: audioreach: fix potential null pointer dereference Thadeu Lima de Souza Cascardo (1): media: uvcvideo: Mark invalid entities with id UVC_INVALID_ENTITY_ID Wang Haoran (1): scsi: target: target_core_configfs: Add length check to avoid buffer overflow

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[PATCH v8 1/3] drm/buddy: Optimize free block management with RB tree

by Arunpravin Paneer Selvam

Replace the freelist (O(n)) used for free block management with a red-black tree, providing more efficient O(log n) search, insert, and delete operations. This improves scalability and performance when managing large numbers of free blocks per order (e.g., hundreds or thousands). In the VK-CTS memory stress subtest, the buddy manager merges fragmented memory and inserts freed blocks into the freelist. Since freelist insertion is O(n), this becomes a bottleneck as fragmentation increases. Benchmarking shows list_insert_sorted() consumes ~52.69% CPU with the freelist, compared to just 0.03% with the RB tree (rbtree_insert.isra.0), despite performing the same sorted insert. This also improves performance in heavily fragmented workloads, such as games or graphics tests that stress memory. As the buddy allocator evolves with new features such as clear-page tracking, the resulting fragmentation and complexity have grown. These RB-tree based design changes are introduced to address that growth and ensure the allocator continues to perform efficiently under fragmented conditions. The RB tree implementation with separate clear/dirty trees provides: - O(n log n) aggregate complexity for all operations instead of O(n^2) - Elimination of soft lockups and system instability - Improved code maintainability and clarity - Better scalability for large memory systems - Predictable performance under fragmentation v3(Matthew): - Remove RB_EMPTY_NODE check in force_merge function. - Rename rb for loop macros to have less generic names and move to .c file. - Make the rb node rb and link field as union. v4(Jani Nikula): - The kernel-doc comment should be "/**" - Move all the rbtree macros to rbtree.h and add parens to ensure correct precedence. v5: - Remove the inline in a .c file (Jani Nikula). v6(Peter Zijlstra): - Add rb_add() function replacing the existing rbtree_insert() code. v7: - A full walk iteration in rbtree is slower than the list (Peter Zijlstra). - The existing rbtree_postorder_for_each_entry_safe macro should be used in scenarios where traversal order is not a critical factor (Christian). v8(Matthew): - Remove the rbtree_is_empty() check in this patch as well. Cc: stable(a)vger.kernel.org Fixes: a68c7eaa7a8f ("drm/amdgpu: Enable clear page functionality") Signed-off-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam(a)amd.com> Reviewed-by: Matthew Auld <matthew.auld(a)intel.com> --- drivers/gpu/drm/drm_buddy.c | 195 ++++++++++++++++++++++-------------- include/drm/drm_buddy.h | 11 +- 2 files changed, 126 insertions(+), 80 deletions(-) diff --git a/drivers/gpu/drm/drm_buddy.c b/drivers/gpu/drm/drm_buddy.c index a94061f373de..c87210a06c31 100644 --- a/drivers/gpu/drm/drm_buddy.c +++ b/drivers/gpu/drm/drm_buddy.c @@ -14,6 +14,8 @@ static struct kmem_cache *slab_blocks; +#define rbtree_get_free_block(node) rb_entry((node), struct drm_buddy_block, rb) + static struct drm_buddy_block *drm_block_alloc(struct drm_buddy *mm, struct drm_buddy_block *parent, unsigned int order, @@ -31,6 +33,8 @@ static struct drm_buddy_block *drm_block_alloc(struct drm_buddy *mm, block->header |= order; block->parent = parent; + RB_CLEAR_NODE(&block->rb); + BUG_ON(block->header & DRM_BUDDY_HEADER_UNUSED); return block; } @@ -41,23 +45,49 @@ static void drm_block_free(struct drm_buddy *mm, kmem_cache_free(slab_blocks, block); } -static void list_insert_sorted(struct drm_buddy *mm, - struct drm_buddy_block *block) +static bool drm_buddy_block_offset_less(const struct drm_buddy_block *block, + const struct drm_buddy_block *node) { - struct drm_buddy_block *node; - struct list_head *head; + return drm_buddy_block_offset(block) < drm_buddy_block_offset(node); +} - head = &mm->free_list[drm_buddy_block_order(block)]; - if (list_empty(head)) { - list_add(&block->link, head); - return; - } +static bool rbtree_block_offset_less(struct rb_node *block, + const struct rb_node *node) +{ + return drm_buddy_block_offset_less(rbtree_get_free_block(block), + rbtree_get_free_block(node)); +} - list_for_each_entry(node, head, link) - if (drm_buddy_block_offset(block) < drm_buddy_block_offset(node)) - break; +static void rbtree_insert(struct drm_buddy *mm, + struct drm_buddy_block *block) +{ + rb_add(&block->rb, + &mm->free_tree[drm_buddy_block_order(block)], + rbtree_block_offset_less); +} + +static void rbtree_remove(struct drm_buddy *mm, + struct drm_buddy_block *block) +{ + struct rb_root *root; + + root = &mm->free_tree[drm_buddy_block_order(block)]; + rb_erase(&block->rb, root); + + RB_CLEAR_NODE(&block->rb); +} + +static struct drm_buddy_block * +rbtree_last_entry(struct drm_buddy *mm, unsigned int order) +{ + struct rb_node *node = rb_last(&mm->free_tree[order]); + + return node ? rb_entry(node, struct drm_buddy_block, rb) : NULL; +} - __list_add(&block->link, node->link.prev, &node->link); +static bool rbtree_is_empty(struct drm_buddy *mm, unsigned int order) +{ + return RB_EMPTY_ROOT(&mm->free_tree[order]); } static void clear_reset(struct drm_buddy_block *block) @@ -70,12 +100,13 @@ static void mark_cleared(struct drm_buddy_block *block) block->header |= DRM_BUDDY_HEADER_CLEAR; } -static void mark_allocated(struct drm_buddy_block *block) +static void mark_allocated(struct drm_buddy *mm, + struct drm_buddy_block *block) { block->header &= ~DRM_BUDDY_HEADER_STATE; block->header |= DRM_BUDDY_ALLOCATED; - list_del(&block->link); + rbtree_remove(mm, block); } static void mark_free(struct drm_buddy *mm, @@ -84,15 +115,16 @@ static void mark_free(struct drm_buddy *mm, block->header &= ~DRM_BUDDY_HEADER_STATE; block->header |= DRM_BUDDY_FREE; - list_insert_sorted(mm, block); + rbtree_insert(mm, block); } -static void mark_split(struct drm_buddy_block *block) +static void mark_split(struct drm_buddy *mm, + struct drm_buddy_block *block) { block->header &= ~DRM_BUDDY_HEADER_STATE; block->header |= DRM_BUDDY_SPLIT; - list_del(&block->link); + rbtree_remove(mm, block); } static inline bool overlaps(u64 s1, u64 e1, u64 s2, u64 e2) @@ -148,7 +180,7 @@ static unsigned int __drm_buddy_free(struct drm_buddy *mm, mark_cleared(parent); } - list_del(&buddy->link); + rbtree_remove(mm, buddy); if (force_merge && drm_buddy_block_is_clear(buddy)) mm->clear_avail -= drm_buddy_block_size(mm, buddy); @@ -179,13 +211,19 @@ static int __force_merge(struct drm_buddy *mm, return -EINVAL; for (i = min_order - 1; i >= 0; i--) { - struct drm_buddy_block *block, *prev; + struct rb_root *root = &mm->free_tree[i]; + struct rb_node *iter; + + iter = rb_last(root); - list_for_each_entry_safe_reverse(block, prev, &mm->free_list[i], link) { - struct drm_buddy_block *buddy; + while (iter) { + struct drm_buddy_block *block, *buddy; u64 block_start, block_end; - if (!block->parent) + block = rbtree_get_free_block(iter); + iter = rb_prev(iter); + + if (!block || !block->parent) continue; block_start = drm_buddy_block_offset(block); @@ -201,15 +239,10 @@ static int __force_merge(struct drm_buddy *mm, WARN_ON(drm_buddy_block_is_clear(block) == drm_buddy_block_is_clear(buddy)); - /* - * If the prev block is same as buddy, don't access the - * block in the next iteration as we would free the - * buddy block as part of the free function. - */ - if (prev == buddy) - prev = list_prev_entry(prev, link); + if (iter == &buddy->rb) + iter = rb_prev(iter); - list_del(&block->link); + rbtree_remove(mm, block); if (drm_buddy_block_is_clear(block)) mm->clear_avail -= drm_buddy_block_size(mm, block); @@ -237,7 +270,7 @@ static int __force_merge(struct drm_buddy *mm, int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size) { unsigned int i; - u64 offset; + u64 offset = 0; if (size < chunk_size) return -EINVAL; @@ -258,14 +291,14 @@ int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size) BUG_ON(mm->max_order > DRM_BUDDY_MAX_ORDER); - mm->free_list = kmalloc_array(mm->max_order + 1, - sizeof(struct list_head), + mm->free_tree = kmalloc_array(mm->max_order + 1, + sizeof(struct rb_root), GFP_KERNEL); - if (!mm->free_list) + if (!mm->free_tree) return -ENOMEM; for (i = 0; i <= mm->max_order; ++i) - INIT_LIST_HEAD(&mm->free_list[i]); + mm->free_tree[i] = RB_ROOT; mm->n_roots = hweight64(size); @@ -273,9 +306,8 @@ int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size) sizeof(struct drm_buddy_block *), GFP_KERNEL); if (!mm->roots) - goto out_free_list; + goto out_free_tree; - offset = 0; i = 0; /* @@ -312,8 +344,8 @@ int drm_buddy_init(struct drm_buddy *mm, u64 size, u64 chunk_size) while (i--) drm_block_free(mm, mm->roots[i]); kfree(mm->roots); -out_free_list: - kfree(mm->free_list); +out_free_tree: + kfree(mm->free_tree); return -ENOMEM; } EXPORT_SYMBOL(drm_buddy_init); @@ -323,7 +355,7 @@ EXPORT_SYMBOL(drm_buddy_init); * * @mm: DRM buddy manager to free * - * Cleanup memory manager resources and the freelist + * Cleanup memory manager resources and the freetree */ void drm_buddy_fini(struct drm_buddy *mm) { @@ -350,7 +382,7 @@ void drm_buddy_fini(struct drm_buddy *mm) WARN_ON(mm->avail != mm->size); kfree(mm->roots); - kfree(mm->free_list); + kfree(mm->free_tree); } EXPORT_SYMBOL(drm_buddy_fini); @@ -383,7 +415,7 @@ static int split_block(struct drm_buddy *mm, clear_reset(block); } - mark_split(block); + mark_split(mm, block); return 0; } @@ -412,7 +444,7 @@ EXPORT_SYMBOL(drm_get_buddy); * @is_clear: blocks clear state * * Reset the clear state based on @is_clear value for each block - * in the freelist. + * in the freetree. */ void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear) { @@ -431,9 +463,9 @@ void drm_buddy_reset_clear(struct drm_buddy *mm, bool is_clear) } for (i = 0; i <= mm->max_order; ++i) { - struct drm_buddy_block *block; + struct drm_buddy_block *block, *tmp; - list_for_each_entry_reverse(block, &mm->free_list[i], link) { + rbtree_postorder_for_each_entry_safe(block, tmp, &mm->free_tree[i], rb) { if (is_clear != drm_buddy_block_is_clear(block)) { if (is_clear) { mark_cleared(block); @@ -639,14 +671,18 @@ get_maxblock(struct drm_buddy *mm, unsigned int order, unsigned int i; for (i = order; i <= mm->max_order; ++i) { + struct rb_node *iter = rb_last(&mm->free_tree[i]); struct drm_buddy_block *tmp_block; - list_for_each_entry_reverse(tmp_block, &mm->free_list[i], link) { - if (block_incompatible(tmp_block, flags)) - continue; + while (iter) { + tmp_block = rbtree_get_free_block(iter); - block = tmp_block; - break; + if (!block_incompatible(tmp_block, flags)) { + block = tmp_block; + break; + } + + iter = rb_prev(iter); } if (!block) @@ -667,7 +703,7 @@ get_maxblock(struct drm_buddy *mm, unsigned int order, } static struct drm_buddy_block * -alloc_from_freelist(struct drm_buddy *mm, +alloc_from_freetree(struct drm_buddy *mm, unsigned int order, unsigned long flags) { @@ -682,14 +718,18 @@ alloc_from_freelist(struct drm_buddy *mm, tmp = drm_buddy_block_order(block); } else { for (tmp = order; tmp <= mm->max_order; ++tmp) { + struct rb_node *iter = rb_last(&mm->free_tree[tmp]); struct drm_buddy_block *tmp_block; - list_for_each_entry_reverse(tmp_block, &mm->free_list[tmp], link) { - if (block_incompatible(tmp_block, flags)) - continue; + while (iter) { + tmp_block = rbtree_get_free_block(iter); - block = tmp_block; - break; + if (!block_incompatible(tmp_block, flags)) { + block = tmp_block; + break; + } + + iter = rb_prev(iter); } if (block) @@ -700,13 +740,9 @@ alloc_from_freelist(struct drm_buddy *mm, if (!block) { /* Fallback method */ for (tmp = order; tmp <= mm->max_order; ++tmp) { - if (!list_empty(&mm->free_list[tmp])) { - block = list_last_entry(&mm->free_list[tmp], - struct drm_buddy_block, - link); - if (block) - break; - } + block = rbtree_last_entry(mm, tmp); + if (block) + break; } if (!block) @@ -771,7 +807,7 @@ static int __alloc_range(struct drm_buddy *mm, if (contains(start, end, block_start, block_end)) { if (drm_buddy_block_is_free(block)) { - mark_allocated(block); + mark_allocated(mm, block); total_allocated += drm_buddy_block_size(mm, block); mm->avail -= drm_buddy_block_size(mm, block); if (drm_buddy_block_is_clear(block)) @@ -849,8 +885,8 @@ static int __alloc_contig_try_harder(struct drm_buddy *mm, { u64 rhs_offset, lhs_offset, lhs_size, filled; struct drm_buddy_block *block; - struct list_head *list; LIST_HEAD(blocks_lhs); + struct rb_node *iter; unsigned long pages; unsigned int order; u64 modify_size; @@ -862,11 +898,14 @@ static int __alloc_contig_try_harder(struct drm_buddy *mm, if (order == 0) return -ENOSPC; - list = &mm->free_list[order]; - if (list_empty(list)) + if (rbtree_is_empty(mm, order)) return -ENOSPC; - list_for_each_entry_reverse(block, list, link) { + iter = rb_last(&mm->free_tree[order]); + + while (iter) { + block = rbtree_get_free_block(iter); + /* Allocate blocks traversing RHS */ rhs_offset = drm_buddy_block_offset(block); err = __drm_buddy_alloc_range(mm, rhs_offset, size, @@ -891,6 +930,8 @@ static int __alloc_contig_try_harder(struct drm_buddy *mm, } /* Free blocks for the next iteration */ drm_buddy_free_list_internal(mm, blocks); + + iter = rb_prev(iter); } return -ENOSPC; @@ -976,7 +1017,7 @@ int drm_buddy_block_trim(struct drm_buddy *mm, list_add(&block->tmp_link, &dfs); err = __alloc_range(mm, &dfs, new_start, new_size, blocks, NULL); if (err) { - mark_allocated(block); + mark_allocated(mm, block); mm->avail -= drm_buddy_block_size(mm, block); if (drm_buddy_block_is_clear(block)) mm->clear_avail -= drm_buddy_block_size(mm, block); @@ -999,8 +1040,8 @@ __drm_buddy_alloc_blocks(struct drm_buddy *mm, return __drm_buddy_alloc_range_bias(mm, start, end, order, flags); else - /* Allocate from freelist */ - return alloc_from_freelist(mm, order, flags); + /* Allocate from freetree */ + return alloc_from_freetree(mm, order, flags); } /** @@ -1017,8 +1058,8 @@ __drm_buddy_alloc_blocks(struct drm_buddy *mm, * alloc_range_bias() called on range limitations, which traverses * the tree and returns the desired block. * - * alloc_from_freelist() called when *no* range restrictions - * are enforced, which picks the block from the freelist. + * alloc_from_freetree() called when *no* range restrictions + * are enforced, which picks the block from the freetree. * * Returns: * 0 on success, error code on failure. @@ -1120,7 +1161,7 @@ int drm_buddy_alloc_blocks(struct drm_buddy *mm, } } while (1); - mark_allocated(block); + mark_allocated(mm, block); mm->avail -= drm_buddy_block_size(mm, block); if (drm_buddy_block_is_clear(block)) mm->clear_avail -= drm_buddy_block_size(mm, block); @@ -1201,10 +1242,10 @@ void drm_buddy_print(struct drm_buddy *mm, struct drm_printer *p) mm->chunk_size >> 10, mm->size >> 20, mm->avail >> 20, mm->clear_avail >> 20); for (order = mm->max_order; order >= 0; order--) { - struct drm_buddy_block *block; + struct drm_buddy_block *block, *tmp; u64 count = 0, free; - list_for_each_entry(block, &mm->free_list[order], link) { + rbtree_postorder_for_each_entry_safe(block, tmp, &mm->free_tree[order], rb) { BUG_ON(!drm_buddy_block_is_free(block)); count++; } diff --git a/include/drm/drm_buddy.h b/include/drm/drm_buddy.h index 513837632b7d..9ee105d4309f 100644 --- a/include/drm/drm_buddy.h +++ b/include/drm/drm_buddy.h @@ -10,6 +10,7 @@ #include <linux/list.h> #include <linux/slab.h> #include <linux/sched.h> +#include <linux/rbtree.h> #include <drm/drm_print.h> @@ -53,7 +54,11 @@ struct drm_buddy_block { * a list, if so desired. As soon as the block is freed with * drm_buddy_free* ownership is given back to the mm. */ - struct list_head link; + union { + struct rb_node rb; + struct list_head link; + }; + struct list_head tmp_link; }; @@ -68,7 +73,7 @@ struct drm_buddy_block { */ struct drm_buddy { /* Maintain a free list for each order. */ - struct list_head *free_list; + struct rb_root *free_tree; /* * Maintain explicit binary tree(s) to track the allocation of the @@ -94,7 +99,7 @@ struct drm_buddy { }; static inline u64 -drm_buddy_block_offset(struct drm_buddy_block *block) +drm_buddy_block_offset(const struct drm_buddy_block *block) { return block->header & DRM_BUDDY_HEADER_OFFSET; } base-commit: a31c6c50da013dcd4de4889d402b47bae552a2e2 -- 2.34.1

2 weeks

1
1
0 0

[PATCH] drm/mediatek: Fix refcounting in mtk_drm_get_all_drm_priv

by Sjoerd Simons

dev_get_drvdata simply returns the driver data part of drm_dev, which has its lifetime bound to the drm_dev. So only drop the reference in the error paths, on success they will get dropped later. Cc: stable(a)vger.kernel.org Fixes: 9ba2556cef1df ("drm/mediatek: clean up driver data initialisation") Signed-off-by: Sjoerd Simons <sjoerd(a)collabora.com> --- drivers/gpu/drm/mediatek/mtk_drm_drv.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_drm_drv.c b/drivers/gpu/drm/mediatek/mtk_drm_drv.c index 7841f59c52ee772dba3de416f410604f5f13eef2..c85fbecce9d6f0ade700e047e067ee7f9250f037 100644 --- a/drivers/gpu/drm/mediatek/mtk_drm_drv.c +++ b/drivers/gpu/drm/mediatek/mtk_drm_drv.c @@ -373,7 +373,7 @@ static int mtk_drm_match(struct device *dev, const void *data) static bool mtk_drm_get_all_drm_priv(struct device *dev) { struct mtk_drm_private *drm_priv = dev_get_drvdata(dev); - struct mtk_drm_private *all_drm_priv[MAX_CRTC]; + struct mtk_drm_private *all_drm_priv[MAX_CRTC] = { NULL, }; struct mtk_drm_private *temp_drm_priv; struct device_node *phandle = dev->parent->of_node; const struct of_device_id *of_id; @@ -399,16 +399,22 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev) continue; temp_drm_priv = dev_get_drvdata(drm_dev); - put_device(drm_dev); - if (!temp_drm_priv) + if (!temp_drm_priv) { + put_device(drm_dev); continue; + } - if (temp_drm_priv->data->main_len) + if (temp_drm_priv->data->main_len) { all_drm_priv[CRTC_MAIN] = temp_drm_priv; - else if (temp_drm_priv->data->ext_len) + } else if (temp_drm_priv->data->ext_len) { all_drm_priv[CRTC_EXT] = temp_drm_priv; - else if (temp_drm_priv->data->third_len) + } else if (temp_drm_priv->data->third_len) { all_drm_priv[CRTC_THIRD] = temp_drm_priv; + } else { + dev_warn(drm_dev, "Could not determine crtc type"); + put_device(drm_dev); + continue; + } if (temp_drm_priv->mtk_drm_bound) cnt++; @@ -427,6 +433,10 @@ static bool mtk_drm_get_all_drm_priv(struct device *dev) return true; } + for (i = 0; i < MAX_CRTC; i++) + if (all_drm_priv[i]) + put_device(all_drm_priv[i]->dev); + return false; } --- base-commit: 22b5e8cde1db67c64b83fc0e4e1ab166cacff246 change-id: 20251002-mtk-drm-refcount-e0f718d9364a Best regards, -- Sjoerd Simons <sjoerd(a)collabora.com>

2 weeks

3
2
0 0

[PATCH] devcoredump: Fix circular locking dependency with devcd->mutex.

by Maarten Lankhorst

The original code causes a circular locking dependency found by lockdep. ====================================================== WARNING: possible circular locking dependency detected 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S U ------------------------------------------------------ xe_fault_inject/5091 is trying to acquire lock: ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660 but task is already holding lock: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&devcd->mutex){+.+.}-{3:3}: mutex_lock_nested+0x4e/0xc0 devcd_data_write+0x27/0x90 sysfs_kf_bin_write+0x80/0xf0 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (kn->active#236){++++}-{0:0}: kernfs_drain+0x1e2/0x200 __kernfs_remove+0xae/0x400 kernfs_remove_by_name_ns+0x5d/0xc0 remove_files+0x54/0x70 sysfs_remove_group+0x3d/0xa0 sysfs_remove_groups+0x2e/0x60 device_remove_attrs+0xc7/0x100 device_del+0x15d/0x3b0 devcd_del+0x19/0x30 process_one_work+0x22b/0x6f0 worker_thread+0x1e8/0x3d0 kthread+0x11c/0x250 ret_from_fork+0x26c/0x2e0 ret_from_fork_asm+0x1a/0x30 -> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}: __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 __flush_work+0x27a/0x660 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 entry_SYSCALL_64_after_hwframe+0x76/0x7e other info that might help us debug this: Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&devcd->mutex); lock(kn->active#236); lock(&devcd->mutex); lock((work_completion)(&(&devcd->del_wk)->work)); *** DEADLOCK *** 5 locks held by xe_fault_inject/5091: #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660 stack backtrace: CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S U 6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)} Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021 Call Trace: <TASK> dump_stack_lvl+0x91/0xf0 dump_stack+0x10/0x20 print_circular_bug+0x285/0x360 check_noncircular+0x135/0x150 ? register_lock_class+0x48/0x4a0 __lock_acquire+0x1661/0x2860 lock_acquire+0xc4/0x2f0 ? __flush_work+0x25d/0x660 ? mark_held_locks+0x46/0x90 ? __flush_work+0x25d/0x660 __flush_work+0x27a/0x660 ? __flush_work+0x25d/0x660 ? trace_hardirqs_on+0x1e/0xd0 ? __pfx_wq_barrier_func+0x10/0x10 flush_delayed_work+0x5d/0xa0 dev_coredump_put+0x63/0xa0 xe_driver_devcoredump_fini+0x12/0x20 [xe] devm_action_release+0x12/0x30 release_nodes+0x3a/0x120 devres_release_all+0x8a/0xd0 device_unbind_cleanup+0x12/0x80 device_release_driver_internal+0x23a/0x280 ? bus_find_device+0xa8/0xe0 device_driver_detach+0x14/0x20 unbind_store+0xaf/0xc0 drv_attr_store+0x21/0x50 sysfs_kf_write+0x4a/0x80 kernfs_fop_write_iter+0x169/0x220 vfs_write+0x293/0x560 ksys_write+0x72/0xf0 __x64_sys_write+0x19/0x30 x64_sys_call+0x2bf/0x2660 do_syscall_64+0x93/0xb60 ? __f_unlock_pos+0x15/0x20 ? __x64_sys_getdents64+0x9b/0x130 ? __pfx_filldir64+0x10/0x10 ? do_syscall_64+0x1a2/0xb60 ? clear_bhb_loop+0x30/0x80 ? clear_bhb_loop+0x30/0x80 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x76e292edd574 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89 RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574 RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063 R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000 </TASK> xe 0000:03:00.0: [drm] Xe device coredump has been deleted. Fixes: 01daccf74832 ("devcoredump : Serialize devcd_del work") Cc: Mukesh Ojha <quic_mojha(a)quicinc.com> Cc: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Cc: Johannes Berg <johannes(a)sipsolutions.net> Cc: "Rafael J. Wysocki" <rafael(a)kernel.org> Cc: Danilo Krummrich <dakr(a)kernel.org> Cc: linux-kernel(a)vger.kernel.org Cc: <stable(a)vger.kernel.org> # v6.1+ Signed-off-by: Maarten Lankhorst <dev(a)lankhorst.se> Cc: Matthew Brost <matthew.brost(a)intel.com> --- drivers/base/devcoredump.c | 136 ++++++++++++++++++++++--------------- 1 file changed, 83 insertions(+), 53 deletions(-) diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c index 03a39c417dc41..ad4bddde12ccb 100644 --- a/drivers/base/devcoredump.c +++ b/drivers/base/devcoredump.c @@ -23,50 +23,46 @@ struct devcd_entry { void *data; size_t datalen; /* - * Here, mutex is required to serialize the calls to del_wk work between - * user/kernel space which happens when devcd is added with device_add() - * and that sends uevent to user space. User space reads the uevents, - * and calls to devcd_data_write() which try to modify the work which is - * not even initialized/queued from devcoredump. + * There are 2 races for which mutex is required. * + * The first race is between device creation and userspace writing to + * schedule immediately destruction. * + * This race is handled by arming the timer before device creation, but + * when device creation fails the timer still exists. * - * cpu0(X) cpu1(Y) + * To solve this, hold the mutex during device_add(), and set + * init_completed on success before releasing the mutex. * - * dev_coredump() uevent sent to user space - * device_add() ======================> user space process Y reads the - * uevents writes to devcd fd - * which results into writes to + * That way the timer will never fire until device_add() is called, + * it will do nothing if init_completed is not set. The timer is also + * cancelled in that case. * - * devcd_data_write() - * mod_delayed_work() - * try_to_grab_pending() - * timer_delete() - * debug_assert_init() - * INIT_DELAYED_WORK() - * schedule_delayed_work() - * - * - * Also, mutex alone would not be enough to avoid scheduling of - * del_wk work after it get flush from a call to devcd_free() - * mentioned as below. - * - * disabled_store() - * devcd_free() - * mutex_lock() devcd_data_write() - * flush_delayed_work() - * mutex_unlock() - * mutex_lock() - * mod_delayed_work() - * mutex_unlock() - * So, delete_work flag is required. + * The second race involves multiple parallel invocations of devcd_free(), + * add a deleted flag so only 1 can call the destructor. */ struct mutex mutex; - bool delete_work; + bool init_completed, deleted; struct module *owner; ssize_t (*read)(char *buffer, loff_t offset, size_t count, void *data, size_t datalen); void (*free)(void *data); + /* + * If nothing interferes and device_add() was returns success, + * del_wk will destroy the device after the timer fires. + * + * Multiple userspace processes can interfere in the working of the timer: + * - Writing to the coredump will reschedule the timer to run immediately, + * if still armed. + * + * This is handled by using "if (cancel_delayed_work()) { + * schedule_delayed_work() }", to prevent re-arming after having + * been previously fired. + * - Writing to /sys/class/devcoredump/disabled will destroy the + * coredump synchronously. + * This is handled by using disable_delayed_work_sync(), and then + * checking if deleted flag is set with &devcd->mutex held. + */ struct delayed_work del_wk; struct device *failing_dev; }; @@ -95,14 +91,27 @@ static void devcd_dev_release(struct device *dev) kfree(devcd); } +static void __devcd_del(struct devcd_entry *devcd) +{ + devcd->deleted = true; + device_del(&devcd->devcd_dev); + put_device(&devcd->devcd_dev); +} + static void devcd_del(struct work_struct *wk) { struct devcd_entry *devcd; + bool init_completed; devcd = container_of(wk, struct devcd_entry, del_wk.work); - device_del(&devcd->devcd_dev); - put_device(&devcd->devcd_dev); + /* devcd->mutex serializes against dev_coredumpm_timeout */ + mutex_lock(&devcd->mutex); + init_completed = devcd->init_completed; + mutex_unlock(&devcd->mutex); + + if (init_completed) + __devcd_del(devcd); } static ssize_t devcd_data_read(struct file *filp, struct kobject *kobj, @@ -122,12 +131,12 @@ static ssize_t devcd_data_write(struct file *filp, struct kobject *kobj, struct device *dev = kobj_to_dev(kobj); struct devcd_entry *devcd = dev_to_devcd(dev); - mutex_lock(&devcd->mutex); - if (!devcd->delete_work) { - devcd->delete_work = true; - mod_delayed_work(system_wq, &devcd->del_wk, 0); - } - mutex_unlock(&devcd->mutex); + /* + * Although it's tempting to use mod_delayed work here, + * that will cause a reschedule if the timer already fired. + */ + if (cancel_delayed_work(&devcd->del_wk)) + schedule_delayed_work(&devcd->del_wk, 0); return count; } @@ -151,11 +160,21 @@ static int devcd_free(struct device *dev, void *data) { struct devcd_entry *devcd = dev_to_devcd(dev); + /* + * To prevent a race with devcd_data_write(), disable work and + * complete manually instead. + * + * We cannot rely on the return value of + * disable_delayed_work_sync() here, because it might be in the + * middle of a cancel_delayed_work + schedule_delayed_work pair. + * + * devcd->mutex here guards against multiple parallel invocations + * of devcd_free(). + */ + disable_delayed_work_sync(&devcd->del_wk); mutex_lock(&devcd->mutex); - if (!devcd->delete_work) - devcd->delete_work = true; - - flush_delayed_work(&devcd->del_wk); + if (!devcd->deleted) + __devcd_del(devcd); mutex_unlock(&devcd->mutex); return 0; } @@ -179,12 +198,10 @@ static ssize_t disabled_show(const struct class *class, const struct class_attri * put_device() <- last reference * error = fn(dev, data) devcd_dev_release() * devcd_free(dev, data) kfree(devcd) - * mutex_lock(&devcd->mutex); * * * In the above diagram, it looks like disabled_store() would be racing with parallelly - * running devcd_del() and result in memory abort while acquiring devcd->mutex which - * is called after kfree of devcd memory after dropping its last reference with + * running devcd_del() and result in memory abort after dropping its last reference with * put_device(). However, this will not happens as fn(dev, data) runs * with its own reference to device via klist_node so it is not its last reference. * so, above situation would not occur. @@ -374,7 +391,7 @@ void dev_coredumpm_timeout(struct device *dev, struct module *owner, devcd->read = read; devcd->free = free; devcd->failing_dev = get_device(dev); - devcd->delete_work = false; + devcd->deleted = false; mutex_init(&devcd->mutex); device_initialize(&devcd->devcd_dev); @@ -383,8 +400,14 @@ void dev_coredumpm_timeout(struct device *dev, struct module *owner, atomic_inc_return(&devcd_count)); devcd->devcd_dev.class = &devcd_class; - mutex_lock(&devcd->mutex); dev_set_uevent_suppress(&devcd->devcd_dev, true); + + /* devcd->mutex prevents devcd_del() completing until init finishes */ + mutex_lock(&devcd->mutex); + devcd->init_completed = false; + INIT_DELAYED_WORK(&devcd->del_wk, devcd_del); + schedule_delayed_work(&devcd->del_wk, timeout); + if (device_add(&devcd->devcd_dev)) goto put_device; @@ -401,13 +424,20 @@ void dev_coredumpm_timeout(struct device *dev, struct module *owner, dev_set_uevent_suppress(&devcd->devcd_dev, false); kobject_uevent(&devcd->devcd_dev.kobj, KOBJ_ADD); - INIT_DELAYED_WORK(&devcd->del_wk, devcd_del); - schedule_delayed_work(&devcd->del_wk, timeout); + + /* + * Safe to run devcd_del() now that we are done with devcd_dev. + * Alternatively we could have taken a ref on devcd_dev before + * dropping the lock. + */ + devcd->init_completed = true; mutex_unlock(&devcd->mutex); return; put_device: - put_device(&devcd->devcd_dev); mutex_unlock(&devcd->mutex); + cancel_delayed_work_sync(&devcd->del_wk); + put_device(&devcd->devcd_dev); + put_module: module_put(owner); free: -- 2.45.2

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Request for Vendor Questionnaire/EOI Form

by Farahiyah

2 weeks, 1 day

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[PATCH] arm64: dts: rockchip: Fix broken tsadc pinctrl binding for rk3588

by Alexander Shiyan

There is no pinctrl "gpio" and "otpout" (probably designed as "output") handling in the tsadc driver. Let's use proper binding "default" and "sleep". Fixes: 32641b8ab1a5 ("arm64: dts: rockchip: add rk3588 thermal sensor") Cc: stable(a)vger.kernel.org Signed-off-by: Alexander Shiyan <eagle.alexander923(a)gmail.com> --- arch/arm64/boot/dts/rockchip/rk3588-base.dtsi | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi index a337f3fb8377..f141065eb69d 100644 --- a/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3588-base.dtsi @@ -2667,9 +2667,9 @@ tsadc: tsadc@fec00000 { rockchip,hw-tshut-temp = <120000>; rockchip,hw-tshut-mode = <0>; /* tshut mode 0:CRU 1:GPIO */ rockchip,hw-tshut-polarity = <0>; /* tshut polarity 0:LOW 1:HIGH */ - pinctrl-0 = <&tsadc_gpio_func>; - pinctrl-1 = <&tsadc_shut>; - pinctrl-names = "gpio", "otpout"; + pinctrl-0 = <&tsadc_shut>; + pinctrl-1 = <&tsadc_gpio_func>; + pinctrl-names = "default", "sleep"; #thermal-sensor-cells = <1>; status = "disabled"; }; -- 2.39.1

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