November 2024 - Linux-stable-mirror

[tip: timers/urgent] posix-timers: Target group sigqueue to current task only if not exiting

by tip-bot2 for Frederic Weisbecker

The following commit has been merged into the timers/urgent branch of tip: Commit-ID: 63dffecfba3eddcf67a8f76d80e0c141f93d44a5 Gitweb: https://git.kernel.org/tip/63dffecfba3eddcf67a8f76d80e0c141f93d44a5 Author: Frederic Weisbecker <frederic(a)kernel.org> AuthorDate: Sat, 23 Nov 2024 00:48:11 +01:00 Committer: Thomas Gleixner <tglx(a)linutronix.de> CommitterDate: Fri, 29 Nov 2024 13:19:09 +01:00 posix-timers: Target group sigqueue to current task only if not exiting A sigqueue belonging to a posix timer, which target is not a specific thread but a whole thread group, is preferrably targeted to the current task if it is part of that thread group. However nothing prevents a posix timer event from queueing such a sigqueue from a reaped yet running task. The interruptible code space between exit_notify() and the final call to schedule() is enough for posix_timer_fn() hrtimer to fire. If that happens while the current task is part of the thread group target, it is proposed to handle it but since its sighand pointer may have been cleared already, the sigqueue is dropped even if there are other tasks running within the group that could handle it. As a result posix timers with thread group wide target may miss signals when some of their threads are exiting. Fix this with verifying that the current task hasn't been through exit_notify() before proposing it as a preferred target so as to ensure that its sighand is still here and stable. complete_signal() might still reconsider the choice and find a better target within the group if current has passed retarget_shared_pending() already. Fixes: bcb7ee79029d ("posix-timers: Prefer delivery of signals to the current thread") Reported-by: Anthony Mallet <anthony.mallet(a)laas.fr> Suggested-by: Oleg Nesterov <oleg(a)redhat.com> Signed-off-by: Frederic Weisbecker <frederic(a)kernel.org> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Acked-by: Oleg Nesterov <oleg(a)redhat.com> Cc: stable(a)vger.kernel.org Link: https://lore.kernel.org/all/20241122234811.60455-1-frederic@kernel.org Closes: https://lore.kernel.org/all/26411.57288.238690.681680@gargle.gargle.HOWL --- kernel/signal.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/signal.c b/kernel/signal.c index 98b65cb..989b1cc 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1959,14 +1959,15 @@ static void posixtimer_queue_sigqueue(struct sigqueue *q, struct task_struct *t, * * Where type is not PIDTYPE_PID, signals must be delivered to the * process. In this case, prefer to deliver to current if it is in - * the same thread group as the target process, which avoids - * unnecessarily waking up a potentially idle task. + * the same thread group as the target process and its sighand is + * stable, which avoids unnecessarily waking up a potentially idle task. */ static inline struct task_struct *posixtimer_get_target(struct k_itimer *tmr) { struct task_struct *t = pid_task(tmr->it_pid, tmr->it_pid_type); - if (t && tmr->it_pid_type != PIDTYPE_PID && same_thread_group(t, current)) + if (t && tmr->it_pid_type != PIDTYPE_PID && + same_thread_group(t, current) && !current->exit_state) t = current; return t; }

4 weeks

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[PATCH] riscv: kprobes: Fix incorrect address calculation

by Nam Cao

p->ainsn.api.insn is a pointer to u32, therefore arithmetic operations are multiplied by four. This is clearly undesirable for this case. Cast it to (void *) first before any calculation. Below is a sample before/after. The dumped memory is two kprobe slots, the first slot has - c.addiw a0, 0x1c (0x7125) - ebreak (0x00100073) and the second slot has: - c.addiw a0, -4 (0x7135) - ebreak (0x00100073) Before this patch: (gdb) x/16xh 0xff20000000135000 0xff20000000135000: 0x7125 0x0000 0x0000 0x0000 0x7135 0x0010 0x0000 0x0000 0xff20000000135010: 0x0073 0x0010 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 After this patch: (gdb) x/16xh 0xff20000000125000 0xff20000000125000: 0x7125 0x0073 0x0010 0x0000 0x7135 0x0073 0x0010 0x0000 0xff20000000125010: 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 0x0000 Fixes: b1756750a397 ("riscv: kprobes: Use patch_text_nosync() for insn slots") Signed-off-by: Nam Cao <namcao(a)linutronix.de> Cc: stable(a)vger.kernel.org --- arch/riscv/kernel/probes/kprobes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/kernel/probes/kprobes.c b/arch/riscv/kernel/probes/kprobes.c index 474a65213657..d2dacea1aedd 100644 --- a/arch/riscv/kernel/probes/kprobes.c +++ b/arch/riscv/kernel/probes/kprobes.c @@ -30,7 +30,7 @@ static void __kprobes arch_prepare_ss_slot(struct kprobe *p) p->ainsn.api.restore = (unsigned long)p->addr + len; patch_text_nosync(p->ainsn.api.insn, &p->opcode, len); - patch_text_nosync(p->ainsn.api.insn + len, &insn, GET_INSN_LENGTH(insn)); + patch_text_nosync((void *)p->ainsn.api.insn + len, &insn, GET_INSN_LENGTH(insn)); } static void __kprobes arch_prepare_simulate(struct kprobe *p) -- 2.39.5

4 weeks

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[PATCH net 14/14] can: mcp251xfd: mcp251xfd_get_tef_len(): work around erratum DS80000789E 6.

by Marc Kleine-Budde

Commit b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") introduced mcp251xfd_get_tef_len() to get the number of unhandled transmit events from the Transmit Event FIFO (TEF). As the TEF has no head index, the driver uses the TX-FIFO's tail index instead, assuming that send frames are completed. When calculating the number of unhandled TEF events, that commit didn't take mcp2518fd erratum DS80000789E 6. into account. According to that erratum, the FIFOCI bits of a FIFOSTA register, here the TX-FIFO tail index might be corrupted. However here it seems the bit indicating that the TX-FIFO is empty (MCP251XFD_REG_FIFOSTA_TFERFFIF) is not correct while the TX-FIFO tail index is. Assume that the TX-FIFO is indeed empty if: - Chip's head and tail index are equal (len == 0). - The TX-FIFO is less than half full. (The TX-FIFO empty case has already been checked at the beginning of this function.) - No free buffers in the TX ring. If the TX-FIFO is assumed to be empty, assume that the TEF is full and return the number of elements in the TX-FIFO (which equals the number of TEF elements). If these assumptions are false, the driver might read to many objects from the TEF. mcp251xfd_handle_tefif_one() checks the sequence numbers and will refuse to process old events. Reported-by: Renjaya Raga Zenta <renjaya.zenta(a)formulatrix.com> Closes: https://patch.msgid.link/CAJ7t6HgaeQ3a_OtfszezU=zB-FqiZXqrnATJ3UujNoQJJf7Gg… Fixes: b8e0ddd36ce9 ("can: mcp251xfd: tef: prepare to workaround broken TEF FIFO tail index erratum") Tested-by: Renjaya Raga Zenta <renjaya.zenta(a)formulatrix.com> Cc: stable(a)vger.kernel.org Link: https://patch.msgid.link/20241126-mcp251xfd-fix-length-calculation-v2-1-c2e… Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de> --- drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c | 29 ++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c index d3ac865933fd..e94321849fd7 100644 --- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c +++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-tef.c @@ -21,6 +21,11 @@ static inline bool mcp251xfd_tx_fifo_sta_empty(u32 fifo_sta) return fifo_sta & MCP251XFD_REG_FIFOSTA_TFERFFIF; } +static inline bool mcp251xfd_tx_fifo_sta_less_than_half_full(u32 fifo_sta) +{ + return fifo_sta & MCP251XFD_REG_FIFOSTA_TFHRFHIF; +} + static inline int mcp251xfd_tef_tail_get_from_chip(const struct mcp251xfd_priv *priv, u8 *tef_tail) @@ -147,7 +152,29 @@ mcp251xfd_get_tef_len(struct mcp251xfd_priv *priv, u8 *len_p) BUILD_BUG_ON(sizeof(tx_ring->obj_num) != sizeof(len)); len = (chip_tx_tail << shift) - (tail << shift); - *len_p = len >> shift; + len >>= shift; + + /* According to mcp2518fd erratum DS80000789E 6. the FIFOCI + * bits of a FIFOSTA register, here the TX-FIFO tail index + * might be corrupted. + * + * However here it seems the bit indicating that the TX-FIFO + * is empty (MCP251XFD_REG_FIFOSTA_TFERFFIF) is not correct + * while the TX-FIFO tail index is. + * + * We assume the TX-FIFO is empty, i.e. all pending CAN frames + * haven been send, if: + * - Chip's head and tail index are equal (len == 0). + * - The TX-FIFO is less than half full. + * (The TX-FIFO empty case has already been checked at the + * beginning of this function.) + * - No free buffers in the TX ring. + */ + if (len == 0 && mcp251xfd_tx_fifo_sta_less_than_half_full(fifo_sta) && + mcp251xfd_get_tx_free(tx_ring) == 0) + len = tx_ring->obj_num; + + *len_p = len; return 0; } -- 2.45.2

4 weeks

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[PATCH net 01/14] can: dev: can_set_termination(): allow sleeping GPIOs

by Marc Kleine-Budde

In commit 6e86a1543c37 ("can: dev: provide optional GPIO based termination support") GPIO based termination support was added. For no particular reason that patch uses gpiod_set_value() to set the GPIO. This leads to the following warning, if the systems uses a sleeping GPIO, i.e. behind an I2C port expander: | WARNING: CPU: 0 PID: 379 at /drivers/gpio/gpiolib.c:3496 gpiod_set_value+0x50/0x6c | CPU: 0 UID: 0 PID: 379 Comm: ip Not tainted 6.11.0-20241016-1 #1 823affae360cc91126e4d316d7a614a8bf86236c Replace gpiod_set_value() by gpiod_set_value_cansleep() to allow the use of sleeping GPIOs. Cc: Nicolai Buchwitz <nb(a)tipi-net.de> Cc: Lino Sanfilippo <l.sanfilippo(a)kunbus.com> Cc: stable(a)vger.kernel.org Reported-by: Leonard Göhrs <l.goehrs(a)pengutronix.de> Tested-by: Leonard Göhrs <l.goehrs(a)pengutronix.de> Fixes: 6e86a1543c37 ("can: dev: provide optional GPIO based termination support") Link: https://patch.msgid.link/20241121-dev-fix-can_set_termination-v1-1-41fa6e29… Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de> --- drivers/net/can/dev/dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c index 6792c14fd7eb..681643ab3780 100644 --- a/drivers/net/can/dev/dev.c +++ b/drivers/net/can/dev/dev.c @@ -468,7 +468,7 @@ static int can_set_termination(struct net_device *ndev, u16 term) else set = 0; - gpiod_set_value(priv->termination_gpio, set); + gpiod_set_value_cansleep(priv->termination_gpio, set); return 0; } base-commit: 9bb88c659673003453fd42e0ddf95c9628409094 -- 2.45.2

4 weeks

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+ mm-respect-mmap-hint-address-when-aligning-for-thp.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm: Respect mmap hint address when aligning for THP has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-respect-mmap-hint-address-when-aligning-for-thp.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: Kalesh Singh <kaleshsingh(a)google.com> Subject: mm: Respect mmap hint address when aligning for THP Date: Mon, 18 Nov 2024 13:46:48 -0800 Commit efa7df3e3bb5 ("mm: align larger anonymous mappings on THP boundaries") updated __get_unmapped_area() to align the start address for the VMA to a PMD boundary if CONFIG_TRANSPARENT_HUGEPAGE=y. It does this by effectively looking up a region that is of size, request_size + PMD_SIZE, and aligning up the start to a PMD boundary. Commit 4ef9ad19e176 ("mm: huge_memory: don't force huge page alignment on 32 bit") opted out of this for 32bit due to regressions in mmap base randomization. Commit d4148aeab412 ("mm, mmap: limit THP alignment of anonymous mappings to PMD-aligned sizes") restricted this to only mmap sizes that are multiples of the PMD_SIZE due to reported regressions in some performance benchmarks -- which seemed mostly due to the reduced spatial locality of related mappings due to the forced PMD-alignment. Another unintended side effect has emerged: When a user specifies an mmap hint address, the THP alignment logic modifies the behavior, potentially ignoring the hint even if a sufficiently large gap exists at the requested hint location. Example Scenario: Consider the following simplified virtual address (VA) space: ... 0x200000-0x400000 --- VMA A 0x400000-0x600000 --- Hole 0x600000-0x800000 --- VMA B ... A call to mmap() with hint=0x400000 and len=0x200000 behaves differently: - Before THP alignment: The requested region (size 0x200000) fits into the gap at 0x400000, so the hint is respected. - After alignment: The logic searches for a region of size 0x400000 (len + PMD_SIZE) starting at 0x400000. This search fails due to the mapping at 0x600000 (VMA B), and the hint is ignored, falling back to arch_get_unmapped_area[_topdown](). In general the hint is effectively ignored, if there is any existing mapping in the below range: [mmap_hint + mmap_size, mmap_hint + mmap_size + PMD_SIZE) This changes the semantics of mmap hint; from ""Respect the hint if a sufficiently large gap exists at the requested location" to "Respect the hint only if an additional PMD-sized gap exists beyond the requested size". This has performance implications for allocators that allocate their heap using mmap but try to keep it "as contiguous as possible" by using the end of the exisiting heap as the address hint. With the new behavior it's more likely to get a much less contiguous heap, adding extra fragmentation and performance overhead. To restore the expected behavior; don't use thp_get_unmapped_area_vmflags() when the user provided a hint address, for anonymous mappings. Note: As Yang Shi pointed out: the issue still remains for filesystems which are using thp_get_unmapped_area() for their get_unmapped_area() op. It is unclear what worklaods will regress for if we ignore THP alignment when the hint address is provided for such file backed mappings -- so this fix will be handled separately. Link: https://lkml.kernel.org/r/20241118214650.3667577-1-kaleshsingh@google.com Fixes: efa7df3e3bb5 ("mm: align larger anonymous mappings on THP boundaries") Signed-off-by: Kalesh Singh <kaleshsingh(a)google.com> Reviewed-by: Rik van Riel <riel(a)surriel.com> Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz> Reviewed-by: David Hildenbrand <david(a)redhat.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Yang Shi <yang(a)os.amperecomputing.com> Cc: Rik van Riel <riel(a)surriel.com> Cc: Ryan Roberts <ryan.roberts(a)arm.com> Cc: Suren Baghdasaryan <surenb(a)google.com> Cc: Minchan Kim <minchan(a)kernel.org> Cc: Hans Boehm <hboehm(a)google.com> Cc: Lokesh Gidra <lokeshgidra(a)google.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/mmap.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/mmap.c~mm-respect-mmap-hint-address-when-aligning-for-thp +++ a/mm/mmap.c @@ -893,6 +893,7 @@ __get_unmapped_area(struct file *file, u if (get_area) { addr = get_area(file, addr, len, pgoff, flags); } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) + && !addr /* no hint */ && IS_ALIGNED(len, PMD_SIZE)) { /* Ensures that larger anonymous mappings are THP aligned. */ addr = thp_get_unmapped_area_vmflags(file, addr, len, _ Patches currently in -mm which might be from kaleshsingh(a)google.com are mm-respect-mmap-hint-address-when-aligning-for-thp.patch

4 weeks

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[PATCH] arch_numa: Restore nid checks before registering a memblock with a node

by Marc Zyngier

Commit 767507654c22 ("arch_numa: switch over to numa_memblks") significantly cleaned up the NUMA registration code, but also dropped a significant check that was refusing to accept to configure a memblock with an invalid nid. On "quality hardware" such as my ThunderX machine, this results in a kernel that dies immediately: [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x431f0a10] [ 0.000000] Linux version 6.12.0-00013-g8920d74cf8db (maz@valley-girl) (gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #3872 SMP PREEMPT Wed Nov 27 15:25:49 GMT 2024 [ 0.000000] KASLR disabled due to lack of seed [ 0.000000] Machine model: Cavium ThunderX CN88XX board [ 0.000000] efi: EFI v2.4 by American Megatrends [ 0.000000] efi: ESRT=0xffce0ff18 SMBIOS 3.0=0xfffb0000 ACPI 2.0=0xffec60000 MEMRESERVE=0xffc905d98 [ 0.000000] esrt: Reserving ESRT space from 0x0000000ffce0ff18 to 0x0000000ffce0ff50. [ 0.000000] earlycon: pl11 at MMIO 0x000087e024000000 (options '115200n8') [ 0.000000] printk: legacy bootconsole [pl11] enabled [ 0.000000] NODE_DATA(0) allocated [mem 0xff6754580-0xff67566bf] [ 0.000000] Unable to handle kernel paging request at virtual address 0000000000001d40 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x0000000096000004 [ 0.000000] EC = 0x25: DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] FSC = 0x04: level 0 translation fault [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 0.000000] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 0.000000] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 0.000000] [0000000000001d40] user address but active_mm is swapper [ 0.000000] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.12.0-00013-g8920d74cf8db #3872 [ 0.000000] Hardware name: Cavium ThunderX CN88XX board (DT) [ 0.000000] pstate: a00000c5 (NzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 0.000000] pc : sparse_init_nid+0x54/0x428 [ 0.000000] lr : sparse_init+0x118/0x240 [ 0.000000] sp : ffff800081da3cb0 [ 0.000000] x29: ffff800081da3cb0 x28: 0000000fedbab10c x27: 0000000000000001 [ 0.000000] x26: 0000000ffee250f8 x25: 0000000000000001 x24: ffff800082102cd0 [ 0.000000] x23: 0000000000000001 x22: 0000000000000000 x21: 00000000001fffff [ 0.000000] x20: 0000000000000001 x19: 0000000000000000 x18: ffffffffffffffff [ 0.000000] x17: 0000000001b00000 x16: 0000000ffd130000 x15: 0000000000000000 [ 0.000000] x14: 00000000003e0000 x13: 00000000000001c8 x12: 0000000000000014 [ 0.000000] x11: ffff800081e82860 x10: ffff8000820fb2c8 x9 : ffff8000820fb490 [ 0.000000] x8 : 0000000000ffed20 x7 : 0000000000000014 x6 : 00000000001fffff [ 0.000000] x5 : 00000000ffffffff x4 : 0000000000000000 x3 : 0000000000000000 [ 0.000000] x2 : 0000000000000000 x1 : 0000000000000040 x0 : 0000000000000007 [ 0.000000] Call trace: [ 0.000000] sparse_init_nid+0x54/0x428 [ 0.000000] sparse_init+0x118/0x240 [ 0.000000] bootmem_init+0x70/0x1c8 [ 0.000000] setup_arch+0x184/0x270 [ 0.000000] start_kernel+0x74/0x670 [ 0.000000] __primary_switched+0x80/0x90 [ 0.000000] Code: f865d804 d37df060 cb030000 d2800003 (b95d4084) [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- while previous kernel versions were able to recognise how brain-damaged the machine is, and only build a fake node. Restoring the check brings back some sanity and a "working" system. Fixes: 767507654c22 ("arch_numa: switch over to numa_memblks") Signed-off-by: Marc Zyngier <maz(a)kernel.org> Cc: Mike Rapoport <rppt(a)kernel.org> Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: Will Deacon <will(a)kernel.org> Cc: Zi Yan <ziy(a)nvidia.com> Cc: Dan Williams <dan.j.williams(a)intel.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: stable(a)vger.kernel.org --- drivers/base/arch_numa.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c index e187016764265..5457248eb0811 100644 --- a/drivers/base/arch_numa.c +++ b/drivers/base/arch_numa.c @@ -207,7 +207,21 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn) static int __init numa_register_nodes(void) { int nid; - + struct memblock_region *mblk; + + /* Check that valid nid is set to memblks */ + for_each_mem_region(mblk) { + int mblk_nid = memblock_get_region_node(mblk); + phys_addr_t start = mblk->base; + phys_addr_t end = mblk->base + mblk->size - 1; + + if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) { + pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n", + mblk_nid, &start, &end); + return -EINVAL; + } + } + /* Finally register nodes. */ for_each_node_mask(nid, numa_nodes_parsed) { unsigned long start_pfn, end_pfn; -- 2.39.2

4 weeks

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[merged] arch_numa-restore-nid-checks-before-registering-a-memblock-with-a-node.patch removed from -mm tree

by Andrew Morton

The quilt patch titled Subject: arch_numa: restore nid checks before registering a memblock with a node has been removed from the -mm tree. Its filename was arch_numa-restore-nid-checks-before-registering-a-memblock-with-a-node.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Marc Zyngier <maz(a)kernel.org> Subject: arch_numa: restore nid checks before registering a memblock with a node Date: Wed, 27 Nov 2024 19:30:00 +0000 Commit 767507654c22 ("arch_numa: switch over to numa_memblks") significantly cleaned up the NUMA registration code, but also dropped a significant check that was refusing to accept to configure a memblock with an invalid nid. On "quality hardware" such as my ThunderX machine, this results in a kernel that dies immediately: [ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x431f0a10] [ 0.000000] Linux version 6.12.0-00013-g8920d74cf8db (maz@valley-girl) (gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40) #3872 SMP PREEMPT Wed Nov 27 15:25:49 GMT 2024 [ 0.000000] KASLR disabled due to lack of seed [ 0.000000] Machine model: Cavium ThunderX CN88XX board [ 0.000000] efi: EFI v2.4 by American Megatrends [ 0.000000] efi: ESRT=0xffce0ff18 SMBIOS 3.0=0xfffb0000 ACPI 2.0=0xffec60000 MEMRESERVE=0xffc905d98 [ 0.000000] esrt: Reserving ESRT space from 0x0000000ffce0ff18 to 0x0000000ffce0ff50. [ 0.000000] earlycon: pl11 at MMIO 0x000087e024000000 (options '115200n8') [ 0.000000] printk: legacy bootconsole [pl11] enabled [ 0.000000] NODE_DATA(0) allocated [mem 0xff6754580-0xff67566bf] [ 0.000000] Unable to handle kernel paging request at virtual address 0000000000001d40 [ 0.000000] Mem abort info: [ 0.000000] ESR = 0x0000000096000004 [ 0.000000] EC = 0x25: DABT (current EL), IL = 32 bits [ 0.000000] SET = 0, FnV = 0 [ 0.000000] EA = 0, S1PTW = 0 [ 0.000000] FSC = 0x04: level 0 translation fault [ 0.000000] Data abort info: [ 0.000000] ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 [ 0.000000] CM = 0, WnR = 0, TnD = 0, TagAccess = 0 [ 0.000000] GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 [ 0.000000] [0000000000001d40] user address but active_mm is swapper [ 0.000000] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP [ 0.000000] Modules linked in: [ 0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.12.0-00013-g8920d74cf8db #3872 [ 0.000000] Hardware name: Cavium ThunderX CN88XX board (DT) [ 0.000000] pstate: a00000c5 (NzCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 0.000000] pc : sparse_init_nid+0x54/0x428 [ 0.000000] lr : sparse_init+0x118/0x240 [ 0.000000] sp : ffff800081da3cb0 [ 0.000000] x29: ffff800081da3cb0 x28: 0000000fedbab10c x27: 0000000000000001 [ 0.000000] x26: 0000000ffee250f8 x25: 0000000000000001 x24: ffff800082102cd0 [ 0.000000] x23: 0000000000000001 x22: 0000000000000000 x21: 00000000001fffff [ 0.000000] x20: 0000000000000001 x19: 0000000000000000 x18: ffffffffffffffff [ 0.000000] x17: 0000000001b00000 x16: 0000000ffd130000 x15: 0000000000000000 [ 0.000000] x14: 00000000003e0000 x13: 00000000000001c8 x12: 0000000000000014 [ 0.000000] x11: ffff800081e82860 x10: ffff8000820fb2c8 x9 : ffff8000820fb490 [ 0.000000] x8 : 0000000000ffed20 x7 : 0000000000000014 x6 : 00000000001fffff [ 0.000000] x5 : 00000000ffffffff x4 : 0000000000000000 x3 : 0000000000000000 [ 0.000000] x2 : 0000000000000000 x1 : 0000000000000040 x0 : 0000000000000007 [ 0.000000] Call trace: [ 0.000000] sparse_init_nid+0x54/0x428 [ 0.000000] sparse_init+0x118/0x240 [ 0.000000] bootmem_init+0x70/0x1c8 [ 0.000000] setup_arch+0x184/0x270 [ 0.000000] start_kernel+0x74/0x670 [ 0.000000] __primary_switched+0x80/0x90 [ 0.000000] Code: f865d804 d37df060 cb030000 d2800003 (b95d4084) [ 0.000000] ---[ end trace 0000000000000000 ]--- [ 0.000000] Kernel panic - not syncing: Attempted to kill the idle task! [ 0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]--- while previous kernel versions were able to recognise how brain-damaged the machine is, and only build a fake node. Restoring the check brings back some sanity and a "working" system. Link: https://lkml.kernel.org/r/20241127193000.3702637-1-maz@kernel.org Fixes: 767507654c22 ("arch_numa: switch over to numa_memblks") Signed-off-by: Marc Zyngier <maz(a)kernel.org> Cc: Mike Rapoport <rppt(a)kernel.org> Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: Will Deacon <will(a)kernel.org> Cc: Zi Yan <ziy(a)nvidia.com> Cc: Dan Williams <dan.j.williams(a)intel.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- drivers/base/arch_numa.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/drivers/base/arch_numa.c~arch_numa-restore-nid-checks-before-registering-a-memblock-with-a-node +++ a/drivers/base/arch_numa.c @@ -207,7 +207,21 @@ static void __init setup_node_data(int n static int __init numa_register_nodes(void) { int nid; + struct memblock_region *mblk; + /* Check that valid nid is set to memblks */ + for_each_mem_region(mblk) { + int mblk_nid = memblock_get_region_node(mblk); + phys_addr_t start = mblk->base; + phys_addr_t end = mblk->base + mblk->size - 1; + + if (mblk_nid == NUMA_NO_NODE || mblk_nid >= MAX_NUMNODES) { + pr_warn("Warning: invalid memblk node %d [mem %pap-%pap]\n", + mblk_nid, &start, &end); + return -EINVAL; + } + } + /* Finally register nodes. */ for_each_node_mask(nid, numa_nodes_parsed) { unsigned long start_pfn, end_pfn; _ Patches currently in -mm which might be from maz(a)kernel.org are

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+ mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm: reinstate ability to map write-sealed memfd mappings read-only has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only.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: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Subject: mm: reinstate ability to map write-sealed memfd mappings read-only Date: Thu, 28 Nov 2024 15:06:17 +0000 Patch series "mm: reinstate ability to map write-sealed memfd mappings read-only". In commit 158978945f31 ("mm: perform the mapping_map_writable() check after call_mmap()") (and preceding changes in the same series) it became possible to mmap() F_SEAL_WRITE sealed memfd mappings read-only. Commit 5de195060b2e ("mm: resolve faulty mmap_region() error path behaviour") unintentionally undid this logic by moving the mapping_map_writable() check before the shmem_mmap() hook is invoked, thereby regressing this change. This series reworks how we both permit write-sealed mappings being mapped read-only and disallow mprotect() from undoing the write-seal, fixing this regression. We also add a regression test to ensure that we do not accidentally regress this in future. Thanks to Julian Orth for reporting this regression. This patch (of 2): In commit 158978945f31 ("mm: perform the mapping_map_writable() check after call_mmap()") (and preceding changes in the same series) it became possible to mmap() F_SEAL_WRITE sealed memfd mappings read-only. This was previously unnecessarily disallowed, despite the man page documentation indicating that it would be, thereby limiting the usefulness of F_SEAL_WRITE logic. We fixed this by adapting logic that existed for the F_SEAL_FUTURE_WRITE seal (one which disallows future writes to the memfd) to also be used for F_SEAL_WRITE. For background - the F_SEAL_FUTURE_WRITE seal clears VM_MAYWRITE for a read-only mapping to disallow mprotect() from overriding the seal - an operation performed by seal_check_write(), invoked from shmem_mmap(), the f_op->mmap() hook used by shmem mappings. By extending this to F_SEAL_WRITE and critically - checking mapping_map_writable() to determine if we may map the memfd AFTER we invoke shmem_mmap() - the desired logic becomes possible. This is because mapping_map_writable() explicitly checks for VM_MAYWRITE, which we will have cleared. Commit 5de195060b2e ("mm: resolve faulty mmap_region() error path behaviour") unintentionally undid this logic by moving the mapping_map_writable() check before the shmem_mmap() hook is invoked, thereby regressing this change. We reinstate this functionality by moving the check out of shmem_mmap() and instead performing it in do_mmap() at the point at which VMA flags are being determined, which seems in any case to be a more appropriate place in which to make this determination. In order to achieve this we rework memfd seal logic to allow us access to this information using existing logic and eliminate the clearing of VM_MAYWRITE from seal_check_write() which we are performing in do_mmap() instead. Link: https://lkml.kernel.org/r/99fc35d2c62bd2e05571cf60d9f8b843c56069e0.17328047… Fixes: 5de195060b2e ("mm: resolve faulty mmap_region() error path behaviour") Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Reported-by: Julian Orth <ju.orth(a)gmail.com> Closes: https://lore.kernel.org/all/CAHijbEUMhvJTN9Xw1GmbM266FXXv=U7s4L_Jem5x3AaPZx… Cc: Jann Horn <jannh(a)google.com> Cc: Liam R. Howlett <Liam.Howlett(a)Oracle.com> Cc: Linus Torvalds <torvalds(a)linux-foundation.org> Cc: Shuah Khan <shuah(a)kernel.org> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- include/linux/memfd.h | 14 +++++++++ include/linux/mm.h | 58 +++++++++++++++++++++++++++------------- mm/memfd.c | 2 - mm/mmap.c | 4 ++ 4 files changed, 59 insertions(+), 19 deletions(-) --- a/include/linux/memfd.h~mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only +++ a/include/linux/memfd.h @@ -7,6 +7,7 @@ #ifdef CONFIG_MEMFD_CREATE extern long memfd_fcntl(struct file *file, unsigned int cmd, unsigned int arg); struct folio *memfd_alloc_folio(struct file *memfd, pgoff_t idx); +unsigned int *memfd_file_seals_ptr(struct file *file); #else static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned int a) { @@ -16,6 +17,19 @@ static inline struct folio *memfd_alloc_ { return ERR_PTR(-EINVAL); } + +static inline unsigned int *memfd_file_seals_ptr(struct file *file) +{ + return NULL; +} #endif +/* Retrieve memfd seals associated with the file, if any. */ +static inline unsigned int memfd_file_seals(struct file *file) +{ + unsigned int *sealsp = memfd_file_seals_ptr(file); + + return sealsp ? *sealsp : 0; +} + #endif /* __LINUX_MEMFD_H */ --- a/include/linux/mm.h~mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only +++ a/include/linux/mm.h @@ -4091,6 +4091,37 @@ void mem_dump_obj(void *object); static inline void mem_dump_obj(void *object) {} #endif +static inline bool is_write_sealed(int seals) +{ + return seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE); +} + +/** + * is_readonly_sealed - Checks whether write-sealed but mapped read-only, + * in which case writes should be disallowing moving + * forwards. + * @seals: the seals to check + * @vm_flags: the VMA flags to check + * + * Returns whether readonly sealed, in which case writess should be disallowed + * going forward. + */ +static inline bool is_readonly_sealed(int seals, vm_flags_t vm_flags) +{ + /* + * Since an F_SEAL_[FUTURE_]WRITE sealed memfd can be mapped as + * MAP_SHARED and read-only, take care to not allow mprotect to + * revert protections on such mappings. Do this only for shared + * mappings. For private mappings, don't need to mask + * VM_MAYWRITE as we still want them to be COW-writable. + */ + if (is_write_sealed(seals) && + ((vm_flags & (VM_SHARED | VM_WRITE)) == VM_SHARED)) + return true; + + return false; +} + /** * seal_check_write - Check for F_SEAL_WRITE or F_SEAL_FUTURE_WRITE flags and * handle them. @@ -4102,24 +4133,15 @@ static inline void mem_dump_obj(void *ob */ static inline int seal_check_write(int seals, struct vm_area_struct *vma) { - if (seals & (F_SEAL_WRITE | F_SEAL_FUTURE_WRITE)) { - /* - * New PROT_WRITE and MAP_SHARED mmaps are not allowed when - * write seals are active. - */ - if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE)) - return -EPERM; - - /* - * Since an F_SEAL_[FUTURE_]WRITE sealed memfd can be mapped as - * MAP_SHARED and read-only, take care to not allow mprotect to - * revert protections on such mappings. Do this only for shared - * mappings. For private mappings, don't need to mask - * VM_MAYWRITE as we still want them to be COW-writable. - */ - if (vma->vm_flags & VM_SHARED) - vm_flags_clear(vma, VM_MAYWRITE); - } + if (!is_write_sealed(seals)) + return 0; + + /* + * New PROT_WRITE and MAP_SHARED mmaps are not allowed when + * write seals are active. + */ + if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_WRITE)) + return -EPERM; return 0; } --- a/mm/memfd.c~mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only +++ a/mm/memfd.c @@ -170,7 +170,7 @@ static int memfd_wait_for_pins(struct ad return error; } -static unsigned int *memfd_file_seals_ptr(struct file *file) +unsigned int *memfd_file_seals_ptr(struct file *file) { if (shmem_file(file)) return &SHMEM_I(file_inode(file))->seals; --- a/mm/mmap.c~mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only +++ a/mm/mmap.c @@ -47,6 +47,7 @@ #include <linux/oom.h> #include <linux/sched/mm.h> #include <linux/ksm.h> +#include <linux/memfd.h> #include <linux/uaccess.h> #include <asm/cacheflush.h> @@ -368,6 +369,7 @@ unsigned long do_mmap(struct file *file, if (file) { struct inode *inode = file_inode(file); + unsigned int seals = memfd_file_seals(file); unsigned long flags_mask; if (!file_mmap_ok(file, inode, pgoff, len)) @@ -408,6 +410,8 @@ unsigned long do_mmap(struct file *file, vm_flags |= VM_SHARED | VM_MAYSHARE; if (!(file->f_mode & FMODE_WRITE)) vm_flags &= ~(VM_MAYWRITE | VM_SHARED); + else if (is_readonly_sealed(seals, vm_flags)) + vm_flags &= ~VM_MAYWRITE; fallthrough; case MAP_PRIVATE: if (!(file->f_mode & FMODE_READ)) _ Patches currently in -mm which might be from lorenzo.stoakes(a)oracle.com are mm-reinstate-ability-to-map-write-sealed-memfd-mappings-read-only.patch selftests-memfd-add-test-for-mapping-write-sealed-memfd-read-only.patch docs-mm-add-vma-locks-documentation.patch docs-mm-add-vma-locks-documentation-v3.patch docs-mm-add-vma-locks-documentation-fix.patch

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+ mm-memcg-declare-do_memsw_account-inline.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: mm: memcg: declare do_memsw_account inline has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-memcg-declare-do_memsw_account-inline.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: John Sperbeck <jsperbeck(a)google.com> Subject: mm: memcg: declare do_memsw_account inline Date: Thu, 28 Nov 2024 12:39:59 -0800 In commit 66d60c428b23 ("mm: memcg: move legacy memcg event code into memcontrol-v1.c"), the static do_memsw_account() function was moved from a .c file to a .h file. Unfortunately, the traditional inline keyword wasn't added. If a file (e.g., a unit test) includes the .h file, but doesn't refer to do_memsw_account(), it will get a warning like: mm/memcontrol-v1.h:41:13: warning: unused function 'do_memsw_account' [-Wunused-function] 41 | static bool do_memsw_account(void) | ^~~~~~~~~~~~~~~~ Link: https://lkml.kernel.org/r/20241128203959.726527-1-jsperbeck@google.com Fixes: 66d60c428b23 ("mm: memcg: move legacy memcg event code into memcontrol-v1.c") Signed-off-by: John Sperbeck <jsperbeck(a)google.com> Acked-by: Roman Gushchin <roman.gushchin(a)linux.dev> Cc: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Muchun Song <muchun.song(a)linux.dev> Cc: Shakeel Butt <shakeel.butt(a)linux.dev> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/memcontrol-v1.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/memcontrol-v1.h~mm-memcg-declare-do_memsw_account-inline +++ a/mm/memcontrol-v1.h @@ -38,7 +38,7 @@ void mem_cgroup_id_put_many(struct mem_c iter = mem_cgroup_iter(NULL, iter, NULL)) /* Whether legacy memory+swap accounting is active */ -static bool do_memsw_account(void) +static inline bool do_memsw_account(void) { return !cgroup_subsys_on_dfl(memory_cgrp_subsys); } _ Patches currently in -mm which might be from jsperbeck(a)google.com are mm-memcg-declare-do_memsw_account-inline.patch

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[PATCH] btrfs: do proper folio cleanup when cow_file_range() failed

by Qu Wenruo

[BUG] When testing with COW fixup marked as BUG_ON() (this is involved with the new pin_user_pages*() change, which should not result new out-of-band dirty pages), I hit a crash triggered by the BUG_ON() from hitting COW fixup path. This BUG_ON() happens just after a failed btrfs_run_delalloc_range(): BTRFS error (device dm-2): failed to run delalloc range, root 348 ino 405 folio 65536 submit_bitmap 6-15 start 90112 len 106496: -28 ------------[ cut here ]------------ kernel BUG at fs/btrfs/extent_io.c:1444! Internal error: Oops - BUG: 00000000f2000800 [#1] SMP CPU: 0 UID: 0 PID: 434621 Comm: kworker/u24:8 Tainted: G OE 6.12.0-rc7-custom+ #86 Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022 Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs] pc : extent_writepage_io+0x2d4/0x308 [btrfs] lr : extent_writepage_io+0x2d4/0x308 [btrfs] Call trace: extent_writepage_io+0x2d4/0x308 [btrfs] extent_writepage+0x218/0x330 [btrfs] extent_write_cache_pages+0x1d4/0x4b0 [btrfs] btrfs_writepages+0x94/0x150 [btrfs] do_writepages+0x74/0x190 filemap_fdatawrite_wbc+0x88/0xc8 start_delalloc_inodes+0x180/0x3b0 [btrfs] btrfs_start_delalloc_roots+0x174/0x280 [btrfs] shrink_delalloc+0x114/0x280 [btrfs] flush_space+0x250/0x2f8 [btrfs] btrfs_async_reclaim_data_space+0x180/0x228 [btrfs] process_one_work+0x164/0x408 worker_thread+0x25c/0x388 kthread+0x100/0x118 ret_from_fork+0x10/0x20 Code: aa1403e1 9402f3ef aa1403e0 9402f36f (d4210000) ---[ end trace 0000000000000000 ]--- [CAUSE] That failure is mostly from cow_file_range(), where we can hit -ENOSPC. Although the -ENOSPC is already a bug related to our space reservation code, let's just focus on the error handling. For example, we have the following dirty range [0, 64K) of an inode, with 4K sector size and 4K page size: 0 16K 32K 48K 64K |///////////////////////////////////////| |#######################################| Where |///| means page are still dirty, and |###| means the extent io tree has EXTENT_DELALLOC flag. - Enter extent_writepage() for page 0 - Enter btrfs_run_delalloc_range() for range [0, 64K) - Enter cow_file_range() for range [0, 64K) - Function btrfs_reserve_extent() only reserved one 16K extent So we created extent map and ordered extent for range [0, 16K) 0 16K 32K 48K 64K |////////|//////////////////////////////| |<- OE ->|##############################| And range [0, 16K) has its delalloc flag cleared. But since we haven't yet submit any bio, involved 4 pages are still dirty. - Function btrfs_reserve_extent() return with -ENOSPC Now we have to run error cleanup, which will clear all EXTENT_DELALLOC* flags and clear the dirty flags for the remaining ranges: 0 16K 32K 48K 64K |////////| | | | | Note that range [0, 16K) still has their pages dirty. - Some time later, writeback are triggered again for the range [0, 16K) since the page range still have dirty flags. - btrfs_run_delalloc_range() will do nothing because there is no EXTENT_DELALLOC flag. - extent_writepage_io() find page 0 has no ordered flag Which falls into the COW fixup path, triggering the BUG_ON(). Unfortunately this error handling bug dates back to the introduction of btrfs. Thankfully with the abuse of cow fixup, at least it won't crash the kernel. [FIX] Instead of immediately unlock the extent and folios, we keep the extent and folios locked until either erroring out or the whole delalloc range finished. When the whole delalloc range finished without error, we just unlock the whole range with PAGE_SET_ORDERED (and PAGE_UNLOCK for !keep_locked cases), with EXTENT_DELALLOC and EXTENT_LOCKED cleared. And those involved folios will be properly submitted, with their dirty flags cleared during submission. For the error path, it will be a little more complex: - The range with ordered extent allocated (range (1)) We only clear the EXTENT_DELALLOC and EXTENT_LOCKED, as the remaining flags are cleaned up by btrfs_mark_ordered_io_finished()->btrfs_finish_one_ordered(). For folios we finish the IO (clear dirty, start writeback and immediately finish the writeback) and unlock the folios. - The range with reserved extent but no ordered extent (range(2)) - The range we never touched (range(3)) For both range (2) and range(3) the behavior is not changed. Now even if cow_file_range() failed halfway with some successfully reserved extents/ordered extents, we will keep all folios clean, so there will be no future writeback triggered on them. Cc: stable(a)vger.kernel.org Signed-off-by: Qu Wenruo <wqu(a)suse.com> --- fs/btrfs/inode.c | 63 ++++++++++++++++++++++++------------------------ 1 file changed, 31 insertions(+), 32 deletions(-) --- The similar bug exists for nocow path too (and other routines like zoned), the fix for nocow will come later after the patch get reviewed. diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 9267861f8ab0..e8232ac7917f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1372,6 +1372,17 @@ static noinline int cow_file_range(struct btrfs_inode *inode, alloc_hint = btrfs_get_extent_allocation_hint(inode, start, num_bytes); + /* + * We're not doing compressed IO, don't unlock the first page + * (which the caller expects to stay locked), don't clear any + * dirty bits and don't set any writeback bits + * + * Do set the Ordered (Private2) bit so we know this page was + * properly setup for writepage. + */ + page_ops = (keep_locked ? 0 : PAGE_UNLOCK); + page_ops |= PAGE_SET_ORDERED; + /* * Relocation relies on the relocated extents to have exactly the same * size as the original extents. Normally writeback for relocation data @@ -1431,6 +1442,10 @@ static noinline int cow_file_range(struct btrfs_inode *inode, file_extent.offset = 0; file_extent.compression = BTRFS_COMPRESS_NONE; + /* + * Locked range will be released either during error clean up or + * after the whole range is finished. + */ lock_extent(&inode->io_tree, start, start + cur_alloc_size - 1, &cached); @@ -1476,21 +1491,6 @@ static noinline int cow_file_range(struct btrfs_inode *inode, btrfs_dec_block_group_reservations(fs_info, ins.objectid); - /* - * We're not doing compressed IO, don't unlock the first page - * (which the caller expects to stay locked), don't clear any - * dirty bits and don't set any writeback bits - * - * Do set the Ordered (Private2) bit so we know this page was - * properly setup for writepage. - */ - page_ops = (keep_locked ? 0 : PAGE_UNLOCK); - page_ops |= PAGE_SET_ORDERED; - - extent_clear_unlock_delalloc(inode, start, start + cur_alloc_size - 1, - locked_folio, &cached, - EXTENT_LOCKED | EXTENT_DELALLOC, - page_ops); if (num_bytes < cur_alloc_size) num_bytes = 0; else @@ -1507,6 +1507,9 @@ static noinline int cow_file_range(struct btrfs_inode *inode, if (ret) goto out_unlock; } + extent_clear_unlock_delalloc(inode, orig_start, end, locked_folio, &cached, + EXTENT_LOCKED | EXTENT_DELALLOC, + page_ops); done: if (done_offset) *done_offset = end; @@ -1527,35 +1530,31 @@ static noinline int cow_file_range(struct btrfs_inode *inode, * We process each region below. */ - clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | - EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; - page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK; - /* * For the range (1). We have already instantiated the ordered extents * for this region. They are cleaned up by * btrfs_cleanup_ordered_extents() in e.g, - * btrfs_run_delalloc_range(). EXTENT_LOCKED | EXTENT_DELALLOC are - * already cleared in the above loop. And, EXTENT_DELALLOC_NEW | - * EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV are handled by the cleanup - * function. + * btrfs_run_delalloc_range(). + * EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV + * are also handled by the cleanup function. * - * However, in case of @keep_locked, we still need to unlock the pages - * (except @locked_folio) to ensure all the pages are unlocked. + * So here we only clear EXTENT_LOCKED and EXTENT_DELALLOC flag, + * and finish the writeback of the involved folios, which will be + * never submitted. */ - if (keep_locked && orig_start < start) { + if (orig_start < start) { + clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC; + page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK; + if (!locked_folio) mapping_set_error(inode->vfs_inode.i_mapping, ret); extent_clear_unlock_delalloc(inode, orig_start, start - 1, locked_folio, NULL, 0, page_ops); } - /* - * At this point we're unlocked, we want to make sure we're only - * clearing these flags under the extent lock, so lock the rest of the - * range and clear everything up. - */ - lock_extent(&inode->io_tree, start, end, NULL); + clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | + EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; + page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK; /* * For the range (2). If we reserved an extent for our delalloc range -- 2.47.0

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Linux-stable-mirror November 2024