| Message ID | 20230724185410.1124082-3-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Handle most file-backed faults under the VMA lock | expand |
Hey, On Mon, Jul 24, 2023 at 07:54:02PM +0100, Matthew Wilcox (Oracle) wrote: > Remove the TCP layering violation by allowing per-VMA locks on all VMAs. > The fault path will immediately fail in handle_mm_fault(). There may be > a small performance reduction from this patch as a little unnecessary work > will be done on each page fault. See later patches for the improvement. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > Reviewed-by: Suren Baghdasaryan <surenb@google.com> > Cc: Arjun Roy <arjunroy@google.com> > Cc: Eric Dumazet <edumazet@google.com> Unless my bisection has gone awry, this is causing boot failures for me in today's linux-next w/ a splat like so. Full log and bisection log below, it reproduces on this hardware using the standard riscv 64-bit defconfig, although my bisection was done with some more debugging stuff enabled. ===================================== WARNING: bad unlock balance detected! 6.5.0-rc3-next-20230725 #1 Not tainted ------------------------------------- modprobe/58 is trying to release lock (&vma->vm_lock->lock) at: [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 but there are no more locks to release! other info that might help us debug this: 1 lock held by modprobe/58: #0: ffffffff8169daa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x2e stack backtrace: CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) Call Trace: [<ffffffff80006b48>] show_stack+0x2c/0x38 [<ffffffff80b49bb2>] dump_stack_lvl+0x60/0x82 [<ffffffff80b49be8>] dump_stack+0x14/0x1c [<ffffffff80089d5a>] print_unlock_imbalance_bug+0x1cc/0x1d6 [<ffffffff80085e4a>] lock_release+0x236/0x3ae [<ffffffff8007e464>] up_read+0x16/0x26 [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 [<ffffffff80004434>] ret_from_exception+0x0/0x64 ------------[ cut here ]------------ DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffffffe7c63c1558, owner = 0x1, curr 0xffffffe7c0add600, list empty WARNING: CPU: 3 PID: 58 at kernel/locking/rwsem.c:1348 __up_read+0x1c2/0x224 Modules linked in: CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) epc : __up_read+0x1c2/0x224 ra : __up_read+0x1c2/0x224 epc : ffffffff8007e636 ra : ffffffff8007e636 sp : ffffffc8002b3df0 gp : ffffffff818ad0f0 tp : ffffffe7c0add600 t0 : ffffffc8002b3ab8 t1 : 0000000000000044 t2 : 5357525f47554245 s0 : ffffffc8002b3e20 s1 : ffffffffffffff00 a0 : b32cfaf25517f300 a1 : b32cfaf25517f300 a2 : b32cfaf25517f300 a3 : c0000000ffffefff a4 : 00000fff00000000 a5 : 0000000000000004 a6 : ffffffff81643e90 a7 : 0000000000000038 s2 : ffffffe7c63c1560 s3 : ffffffff81ae3578 s4 : ffffffe7c63c1558 s5 : ffffffc8002b3ee0 s6 : 0000000000000254 s7 : ffffffe7c63c05a0 s8 : 0000003f97687780 s9 : ffffffffeffffef5 s10: 000000006474e553 s11: 0000000000000000 t3 : ffffffff8259430f t4 : ffffffff8259430f t5 : ffffffff82594310 t6 : ffffffff8259430f status: 0000000200000120 badaddr: 0000000000000000 cause: 0000000000000003 [<ffffffff8007e636>] __up_read+0x1c2/0x224 [<ffffffff8007e46a>] up_read+0x1c/0x26 [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 [<ffffffff80004434>] ret_from_exception+0x0/0x64 irq event stamp: 371 hardirqs last enabled at (371): [<ffffffff8000d862>] handle_page_fault+0x36/0x3a4 hardirqs last disabled at (370): [<ffffffff80b4aef6>] irqentry_enter+0x16/0x4c softirqs last enabled at (180): [<ffffffff80b56566>] __do_softirq+0x57e/0x66e softirqs last disabled at (173): [<ffffffff8001f288>] __irq_exit_rcu+0x8c/0x14c ---[ end trace 0000000000000000 ]--- Thanks, Conor. git bisect start # status: waiting for both good and bad commits # good: [06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5] Linux 6.5-rc1 git bisect good 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 # status: waiting for bad commit, 1 good commit known # bad: [1e25dd7772483f477f79986d956028e9f47f990a] Add linux-next specific files for 20230725 git bisect bad 1e25dd7772483f477f79986d956028e9f47f990a # bad: [73002c8a551db94daa4124dbe61a3340999c556e] Merge branch 'master' of git://linuxtv.org/mchehab/media-next.git git bisect bad 73002c8a551db94daa4124dbe61a3340999c556e # bad: [c37659958e0ff5aaffae86df9e696638f58cd3a3] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/joel/bmc.git git bisect bad c37659958e0ff5aaffae86df9e696638f58cd3a3 # good: [bdd1d82e7d02bd2764a68a5cc54533dfc2ba452a] Merge tag 'io_uring-6.5-2023-07-21' of git://git.kernel.dk/linux git bisect good bdd1d82e7d02bd2764a68a5cc54533dfc2ba452a # good: [d7b4fea201483d40b7cb1f522915531c6e6b168b] mm/page_io: convert count_swpout_vm_event() to take in a folio git bisect good d7b4fea201483d40b7cb1f522915531c6e6b168b # good: [46dce626e248cc91b0612f7c6c31b15f48899465] Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git git bisect good 46dce626e248cc91b0612f7c6c31b15f48899465 # bad: [e3fb201f858b63a7abf71b5bb563923b6424b98a] Merge branch 'mm-nonmm-unstable' into mm-everything git bisect bad e3fb201f858b63a7abf71b5bb563923b6424b98a # good: [1e0fb16464b68936b1b901a7b908c37d6f587b7c] arm64: smccc: replace custom COUNT_ARGS() & CONCATENATE() implementations git bisect good 1e0fb16464b68936b1b901a7b908c37d6f587b7c # good: [de32a89e11bab2e9c8c881fbbbad84a492d5ce9c] mm: set up vma iterator for vma_iter_prealloc() calls git bisect good de32a89e11bab2e9c8c881fbbbad84a492d5ce9c # bad: [add29438034569277ab967199af39fe42a4d858c] mm: handle PUD faults under the VMA lock git bisect bad add29438034569277ab967199af39fe42a4d858c # good: [ecc821b0404e19eebf393f7a5a73d80c3faa69e4] maple_tree: reduce resets during store setup git bisect good ecc821b0404e19eebf393f7a5a73d80c3faa69e4 # good: [4e9c4f4a2949a2b47917647283799bb5952f2290] mm: remove CONFIG_PER_VMA_LOCK ifdefs git bisect good 4e9c4f4a2949a2b47917647283799bb5952f2290 # bad: [9a709e2cca6097f66aaba411bd8758cf43a39eb9] mm: move FAULT_FLAG_VMA_LOCK check from handle_mm_fault() git bisect bad 9a709e2cca6097f66aaba411bd8758cf43a39eb9 # bad: [78b696bb953cb0b553e1cf9084a6e09580aa4e2a] mm: allow per-VMA locks on file-backed VMAs git bisect bad 78b696bb953cb0b553e1cf9084a6e09580aa4e2a # first bad commit: [78b696bb953cb0b553e1cf9084a6e09580aa4e2a] mm: allow per-VMA locks on file-backed VMAs [ 0.000000] Linux version 6.5.0-rc3-00283-g78b696bb953c (conor@wendy) (ClangBuiltLinux clang version 15.0.7 (/home/ conor/stuff/dev/llvm/clang 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a), ClangBuiltLinux LLD 15.0.7) #1 SMP PREEMPT @666 [ 0.000000] Machine model: Microchip PolarFire-SoC Icicle Kit [ 0.000000] SBI specification v1.0 detected [ 0.000000] SBI implementation ID=0x1 Version=0x10002 [ 0.000000] SBI TIME extension detected [ 0.000000] SBI IPI extension detected [ 0.000000] SBI RFENCE extension detected [ 0.000000] SBI SRST extension detected [ 0.000000] earlycon: ns16550a0 at MMIO32 0x0000000020100000 (options '115200n8') [ 0.000000] printk: bootconsole [ns16550a0] enabled [ 0.000000] printk: debug: skip boot console de-registration. [ 0.000000] efi: UEFI not found. [ 0.000000] OF: reserved mem: 0x00000000bfc00000..0x00000000bfffffff (4096 KiB) nomap non-reusable region@BFC00000 [ 0.000000] Zone ranges: [ 0.000000] DMA32 [mem 0x0000000080000000-0x00000000ffffffff] [ 0.000000] Normal [mem 0x0000000100000000-0x000000107fffffff] [ 0.000000] Movable zone start for each node [ 0.000000] Early memory node ranges [ 0.000000] node 0: [mem 0x0000000080000000-0x00000000bfbfffff] [ 0.000000] node 0: [mem 0x00000000bfc00000-0x00000000bfffffff] [ 0.000000] node 0: [mem 0x0000001040000000-0x000000107fffffff] [ 0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000107fffffff] [ 0.000000] SBI HSM extension detected [ 0.000000] CPU with hartid=0 is not available [ 0.000000] riscv: base ISA extensions acdfim [ 0.000000] riscv: ELF capabilities acdfim [ 0.000000] percpu: Embedded 30 pages/cpu s84320 r8192 d30368 u122880 [ 0.000000] Kernel command line: earlycon keep_bootcon root=/dev/mmcblk1p2 rootdelay=10 reboot=cold [ 0.000000] Dentry cache hash table entries: 262144 (order: 9, 2097152 bytes, linear) [ 0.000000] Inode-cache hash table entries: 131072 (order: 8, 1048576 bytes, linear) [ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 517120 [ 0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off [ 0.000000] software IO TLB: area num 4. [ 0.000000] software IO TLB: mapped [mem 0x00000000bbc00000-0x00000000bfc00000] (64MB) [ 0.000000] Virtual kernel memory layout: [ 0.000000] fixmap : 0xffffffc6fea00000 - 0xffffffc6ff000000 (6144 kB) [ 0.000000] pci io : 0xffffffc6ff000000 - 0xffffffc700000000 ( 16 MB) [ 0.000000] vmemmap : 0xffffffc700000000 - 0xffffffc800000000 (4096 MB) [ 0.000000] vmalloc : 0xffffffc800000000 - 0xffffffd800000000 ( 64 GB) [ 0.000000] modules : 0xffffffff025d4000 - 0xffffffff80000000 (2010 MB) [ 0.000000] lowmem : 0xffffffd800000000 - 0xffffffe800000000 ( 64 GB) [ 0.000000] kernel : 0xffffffff80000000 - 0xffffffffffffffff (2047 MB) [ 0.000000] Memory: 1913560K/2097152K available (11570K kernel code, 5054K rwdata, 4096K rodata, 6069K init, 11226K bss, 183592K reserved, 0K cma-reserved) [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1 [ 0.000000] trace event string verifier disabled [ 0.000000] Running RCU self tests [ 0.000000] Running RCU synchronous self tests [ 0.000000] rcu: Preemptible hierarchical RCU implementation. [ 0.000000] rcu: RCU lockdep checking is enabled. [ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=4. [ 0.000000] rcu: RCU debug extended QS entry/exit. [ 0.000000] Trampoline variant of Tasks RCU enabled. [ 0.000000] Tracing variant of Tasks RCU enabled. [ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies. [ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4 [ 0.000000] Running RCU synchronous self tests [ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0 [ 0.000000] riscv-intc: unable to find hart id for /cpus/cpu@0/interrupt-controller [ 0.000000] riscv-intc: 64 local interrupts mapped [ 0.000000] plic: interrupt-controller@c000000: mapped 186 interrupts with 4 handlers for 9 contexts. [ 0.000000] riscv: providing IPIs using SBI IPI extension [ 0.000000] rcu: srcu_init: Setting srcu_struct sizes based on contention. [ 0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x1d854df40, max_idle_ns: 3526361616960 ns [ 0.000003] sched_clock: 64 bits at 1000kHz, resolution 1000ns, wraps every 2199023255500ns [ 0.010570] Console: colour dummy device 80x25 [ 0.015820] printk: console [tty0] enabled [ 0.020660] Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar [ 0.029527] ... MAX_LOCKDEP_SUBCLASSES: 8 [ 0.034262] ... MAX_LOCK_DEPTH: 48 [ 0.039096] ... MAX_LOCKDEP_KEYS: 8192 [ 0.044121] ... CLASSHASH_SIZE: 4096 [ 0.049148] ... MAX_LOCKDEP_ENTRIES: 32768 [ 0.054277] ... MAX_LOCKDEP_CHAINS: 65536 [ 0.059407] ... CHAINHASH_SIZE: 32768 [ 0.064539] memory used by lock dependency info: 6493 kB [ 0.070744] memory used for stack traces: 4224 kB [ 0.076263] per task-struct memory footprint: 1920 bytes [ 0.082662] Calibrating delay loop (skipped), value calculated using timer frequency.. 2.00 BogoMIPS (lpj=4000) [ 0.094225] pid_max: default: 32768 minimum: 301 [ 0.100802] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) [ 0.109469] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) [ 0.125003] Running RCU synchronous self tests [ 0.130214] Running RCU synchronous self tests [ 0.137709] CPU node for /cpus/cpu@0 exist but the possible cpu range is :0-3 [ 0.155633] RCU Tasks: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. [ 0.164714] RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. [ 0.174340] Running RCU-tasks wait API self tests [ 0.286157] riscv: ELF compat mode unsupported [ 0.286208] ASID allocator disabled (0 bits) [ 0.296532] Callback from call_rcu_tasks_trace() invoked. [ 0.304124] rcu: Hierarchical SRCU implementation. [ 0.309791] rcu: Max phase no-delay instances is 1000. [ 0.321671] EFI services will not be available. [ 0.329990] smp: Bringing up secondary CPUs ... [ 0.354947] smp: Brought up 1 node, 4 CPUs [ 0.365578] devtmpfs: initialized [ 0.410073] Running RCU synchronous self tests [ 0.416094] Running RCU synchronous self tests [ 0.421843] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns [ 0.433116] futex hash table entries: 1024 (order: 5, 131072 bytes, linear) [ 0.442918] pinctrl core: initialized pinctrl subsystem [ 0.456687] NET: Registered PF_NETLINK/PF_ROUTE protocol family [ 0.468413] DMA: preallocated 256 KiB GFP_KERNEL pool for atomic allocations [ 0.476749] DMA: preallocated 256 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations [ 0.492183] cpuidle: using governor menu [ 0.558914] Callback from call_rcu_tasks() invoked. [ 0.613189] HugeTLB: registered 2.00 MiB page size, pre-allocated 0 pages [ 0.621137] HugeTLB: 0 KiB vmemmap can be freed for a 2.00 MiB page [ 0.635532] ACPI: Interpreter disabled. [ 0.659634] SCSI subsystem initialized [ 0.667627] usbcore: registered new interface driver usbfs [ 0.674440] usbcore: registered new interface driver hub [ 0.680969] usbcore: registered new device driver usb [ 0.690490] FPGA manager framework [ 0.703508] vgaarb: loaded [ 0.708569] clocksource: Switched to clocksource riscv_clocksource [ 0.723150] pnp: PnP ACPI: disabled [ 0.809949] NET: Registered PF_INET protocol family [ 0.818618] IP idents hash table entries: 32768 (order: 6, 262144 bytes, linear) [ 0.839293] tcp_listen_portaddr_hash hash table entries: 1024 (order: 4, 73728 bytes, linear) [ 0.850714] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear) [ 0.859721] TCP established hash table entries: 16384 (order: 5, 131072 bytes, linear) [ 0.872260] TCP bind hash table entries: 16384 (order: 9, 2359296 bytes, linear) [ 0.902395] TCP: Hash tables configured (established 16384 bind 16384) [ 0.911840] UDP hash table entries: 1024 (order: 5, 163840 bytes, linear) [ 0.921420] UDP-Lite hash table entries: 1024 (order: 5, 163840 bytes, linear) [ 0.932233] NET: Registered PF_UNIX/PF_LOCAL protocol family [ 0.943727] RPC: Registered named UNIX socket transport module. [ 0.950879] RPC: Registered udp transport module. [ 0.956374] RPC: Registered tcp transport module. [ 0.961926] RPC: Registered tcp-with-tls transport module. [ 0.968707] RPC: Registered tcp NFSv4.1 backchannel transport module. [ 0.976198] PCI: CLS 0 bytes, default 64 [ 0.985222] Unpacking initramfs... [ 1.000909] workingset: timestamp_bits=62 max_order=19 bucket_order=0 [ 1.016047] NFS: Registering the id_resolver key type [ 1.022604] Key type id_resolver registered [ 1.027625] Key type id_legacy registered [ 1.032619] nfs4filelayout_init: NFSv4 File Layout Driver Registering... [ 1.040698] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering... [ 1.050868] 9p: Installing v9fs 9p2000 file system support [ 1.059351] NET: Registered PF_ALG protocol family [ 1.065759] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 246) [ 1.074615] io scheduler mq-deadline registered [ 1.079954] io scheduler kyber registered [ 1.084855] io scheduler bfq registered [ 2.691196] String selftests succeeded [ 2.695696] test_string_helpers: Running tests... [ 2.735759] microchip-pcie 3000000000.pcie: host bridge /pcie@3000000000 ranges: [ 2.744646] microchip-pcie 3000000000.pcie: MEM 0x3008000000..0x3087ffffff -> 0x0008000000 [ 2.754854] microchip-pcie 3000000000.pcie: IB MEM 0x0000000000..0x00ffffffff -> 0x0000000000 [ 2.793603] microchip-pcie 3000000000.pcie: ECAM at [mem 0x3000000000-0x3007ffffff] for [bus 00-7f] [ 2.806599] microchip-pcie 3000000000.pcie: PCI host bridge to bus 0000:00 [ 2.814622] pci_bus 0000:00: root bus resource [bus 00-7f] [ 2.821060] pci_bus 0000:00: root bus resource [mem 0x3008000000-0x3087ffffff] (bus address [0x08000000-0x87ffffff] ) [ 2.833923] pci 0000:00:00.0: [11aa:1556] type 01 class 0x000604 [ 2.841032] pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x7fffffff 64bit pref] [ 2.850230] pci 0000:00:00.0: supports D1 D2 [ 2.855282] pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot D3cold [ 2.918454] pci_bus 0000:01: busn_res: [bus 01-7f] end is updated to 01 [ 2.926316] pci 0000:00:00.0: BAR 0: no space for [mem size 0x80000000 64bit pref] [ 2.935124] pci 0000:00:00.0: BAR 0: failed to assign [mem size 0x80000000 64bit pref] [ 2.944337] pci 0000:00:00.0: BAR 8: assigned [mem 0x3008000000-0x30081fffff] [ 2.952729] pci 0000:00:00.0: BAR 9: assigned [mem 0x3008200000-0x30083fffff 64bit pref] [ 2.962291] pci 0000:00:00.0: BAR 7: no space for [io size 0x1000] [ 2.969658] pci 0000:00:00.0: BAR 7: failed to assign [io size 0x1000] [ 2.977402] pci 0000:00:00.0: PCI bridge to [bus 01] [ 2.983258] pci 0000:00:00.0: bridge window [mem 0x3008000000-0x30081fffff] [ 2.991555] pci 0000:00:00.0: bridge window [mem 0x3008200000-0x30083fffff 64bit pref] [ 3.012105] CCACHE: 4 banks, 16 ways, sets/bank=512, bytes/block=64 [ 3.019534] CCACHE: Index of the largest way enabled: 11 [ 3.553216] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled [ 3.599227] 20100000.serial: ttyS1 at MMIO 0x20100000 (irq = 53, base_baud = 9375000) is a 16550A [ 3.610933] printk: console [ttyS1] enabled [ 3.610933] printk: console [ttyS1] enabled [ 3.635869] 20102000.serial: ttyS2 at MMIO 0x20102000 (irq = 54, base_baud = 9375000) is a 16550A [ 3.670527] 20104000.serial: ttyS3 at MMIO 0x20104000 (irq = 55, base_baud = 9375000) is a 16550A [ 3.706515] 20106000.serial: ttyS0 at MMIO 0x20106000 (irq = 56, base_baud = 9375000) is a 16550A [ 3.823007] loop: module loaded [ 3.839186] zram: Added device: zram0 [ 3.867557] microchip-corespi 20108000.spi: Registered SPI controller 0 [ 3.887509] microchip-corespi 20109000.spi: Registered SPI controller 1 [ 5.062117] macb 20110000.ethernet eth0: Cadence GEM rev 0x0107010c at 0x20110000 irq 60 (00:04:a3:bf:d2:70) [ 6.106111] Freeing initrd memory: 25480K [ 6.124243] [ 6.127470] ===================================== [ 6.137414] WARNING: bad unlock balance detected! [ 6.147364] 6.5.0-rc3-next-20230725 #1 Not tainted [ 6.157500] ------------------------------------- [ 6.167447] modprobe/58 is trying to release lock (&vma->vm_lock->lock) at: [ 6.182194] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 [ 6.193279] but there are no more locks to release! [ 6.203590] [ 6.203590] other info that might help us debug this: [ 6.217392] 1 lock held by modprobe/58: [ 6.225516] #0: ffffffff8169daa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x2e [ 6.243441] [ 6.243441] stack backtrace: [ 6.252662] CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 [ 6.268319] Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) [ 6.281383] Call Trace: [ 6.286563] [<ffffffff80006b48>] show_stack+0x2c/0x38 [ 6.297274] [<ffffffff80b49bb2>] dump_stack_lvl+0x60/0x82 [ 6.308723] [<ffffffff80b49be8>] dump_stack+0x14/0x1c [ 6.319417] [<ffffffff80089d5a>] print_unlock_imbalance_bug+0x1cc/0x1d6 [ 6.333417] [<ffffffff80085e4a>] lock_release+0x236/0x3ae [ 6.344867] [<ffffffff8007e464>] up_read+0x16/0x26 [ 6.355013] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 [ 6.366072] [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 [ 6.378415] [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 [ 6.389656] [<ffffffff80004434>] ret_from_exception+0x0/0x64 [ 6.401771] ------------[ cut here ]------------ [ 6.411655] DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffffffe7c63c1558, owner = 0x1, curr 0xffffffe7c0add600, list empty [ 6.439789] WARNING: CPU: 3 PID: 58 at kernel/locking/rwsem.c:1348 __up_read+0x1c2/0x224 [ 6.439840] Modules linked in: [ 6.439855] CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 [ 6.439884] Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) [ 6.439896] epc : __up_read+0x1c2/0x224 [ 6.439923] ra : __up_read+0x1c2/0x224 [ 6.439947] epc : ffffffff8007e636 ra : ffffffff8007e636 sp : ffffffc8002b3df0 [ 6.439966] gp : ffffffff818ad0f0 tp : ffffffe7c0add600 t0 : ffffffc8002b3ab8 [ 6.439986] t1 : 0000000000000044 t2 : 5357525f47554245 s0 : ffffffc8002b3e20 [ 6.440004] s1 : ffffffffffffff00 a0 : b32cfaf25517f300 a1 : b32cfaf25517f300 [ 6.440023] a2 : b32cfaf25517f300 a3 : c0000000ffffefff a4 : 00000fff00000000 [ 6.440042] a5 : 0000000000000004 a6 : ffffffff81643e90 a7 : 0000000000000038 [ 6.440060] s2 : ffffffe7c63c1560 s3 : ffffffff81ae3578 s4 : ffffffe7c63c1558 [ 6.440079] s5 : ffffffc8002b3ee0 s6 : 0000000000000254 s7 : ffffffe7c63c05a0 [ 6.440098] s8 : 0000003f97687780 s9 : ffffffffeffffef5 s10: 000000006474e553 [ 6.440117] s11: 0000000000000000 t3 : ffffffff8259430f t4 : ffffffff8259430f [ 6.440136] t5 : ffffffff82594310 t6 : ffffffff8259430f [ 6.440151] status: 0000000200000120 badaddr: 0000000000000000 cause: 0000000000000003 [ 6.440169] [<ffffffff8007e636>] __up_read+0x1c2/0x224 [ 6.440201] [<ffffffff8007e46a>] up_read+0x1c/0x26 [ 6.440229] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 [ 6.440255] [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 [ 6.440282] [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 [ 6.440309] [<ffffffff80004434>] ret_from_exception+0x0/0x64 [ 6.440339] irq event stamp: 371 [ 6.440347] hardirqs last enabled at (371): [<ffffffff8000d862>] handle_page_fault+0x36/0x3a4 [ 6.440377] hardirqs last disabled at (370): [<ffffffff80b4aef6>] irqentry_enter+0x16/0x4c [ 6.440407] softirqs last enabled at (180): [<ffffffff80b56566>] __do_softirq+0x57e/0x66e [ 6.440453] softirqs last disabled at (173): [<ffffffff8001f288>] __irq_exit_rcu+0x8c/0x14c [ 6.440494] ---[ end trace 0000000000000000 ]---
On Tue, Jul 25, 2023 at 5:58 AM Conor Dooley <conor.dooley@microchip.com> wrote: > > Hey, > > On Mon, Jul 24, 2023 at 07:54:02PM +0100, Matthew Wilcox (Oracle) wrote: > > Remove the TCP layering violation by allowing per-VMA locks on all VMAs. > > The fault path will immediately fail in handle_mm_fault(). There may be > > a small performance reduction from this patch as a little unnecessary work > > will be done on each page fault. See later patches for the improvement. > > > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > > Reviewed-by: Suren Baghdasaryan <surenb@google.com> > > Cc: Arjun Roy <arjunroy@google.com> > > Cc: Eric Dumazet <edumazet@google.com> > > Unless my bisection has gone awry, this is causing boot failures for me > in today's linux-next w/ a splat like so. This patch requires [1] to work correctly. It follows the rule introduced in [1] that anyone returning VM_FAULT_RETRY should also do vma_end_read(). [1] is merged into mm-unstable but has not reached linux-next yet, it seems. [1] https://lore.kernel.org/all/20230630211957.1341547-4-surenb@google.com/ > Full log and bisection log below, it reproduces on this hardware using > the standard riscv 64-bit defconfig, although my bisection was done with > some more debugging stuff enabled. > > ===================================== > WARNING: bad unlock balance detected! > 6.5.0-rc3-next-20230725 #1 Not tainted > ------------------------------------- > modprobe/58 is trying to release lock (&vma->vm_lock->lock) at: > [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > but there are no more locks to release! > > other info that might help us debug this: > 1 lock held by modprobe/58: > #0: ffffffff8169daa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x2e > > stack backtrace: > CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 > Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) > Call Trace: > [<ffffffff80006b48>] show_stack+0x2c/0x38 > [<ffffffff80b49bb2>] dump_stack_lvl+0x60/0x82 > [<ffffffff80b49be8>] dump_stack+0x14/0x1c > [<ffffffff80089d5a>] print_unlock_imbalance_bug+0x1cc/0x1d6 > [<ffffffff80085e4a>] lock_release+0x236/0x3ae > [<ffffffff8007e464>] up_read+0x16/0x26 > [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 > [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 > [<ffffffff80004434>] ret_from_exception+0x0/0x64 > ------------[ cut here ]------------ > DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffffffe7c63c1558, owner = 0x1, curr 0xffffffe7c0add600, list empty > WARNING: CPU: 3 PID: 58 at kernel/locking/rwsem.c:1348 __up_read+0x1c2/0x224 > Modules linked in: > CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 > Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) > epc : __up_read+0x1c2/0x224 > ra : __up_read+0x1c2/0x224 > epc : ffffffff8007e636 ra : ffffffff8007e636 sp : ffffffc8002b3df0 > gp : ffffffff818ad0f0 tp : ffffffe7c0add600 t0 : ffffffc8002b3ab8 > t1 : 0000000000000044 t2 : 5357525f47554245 s0 : ffffffc8002b3e20 > s1 : ffffffffffffff00 a0 : b32cfaf25517f300 a1 : b32cfaf25517f300 > a2 : b32cfaf25517f300 a3 : c0000000ffffefff a4 : 00000fff00000000 > a5 : 0000000000000004 a6 : ffffffff81643e90 a7 : 0000000000000038 > s2 : ffffffe7c63c1560 s3 : ffffffff81ae3578 s4 : ffffffe7c63c1558 > s5 : ffffffc8002b3ee0 s6 : 0000000000000254 s7 : ffffffe7c63c05a0 > s8 : 0000003f97687780 s9 : ffffffffeffffef5 s10: 000000006474e553 > s11: 0000000000000000 t3 : ffffffff8259430f t4 : ffffffff8259430f > t5 : ffffffff82594310 t6 : ffffffff8259430f > status: 0000000200000120 badaddr: 0000000000000000 cause: 0000000000000003 > [<ffffffff8007e636>] __up_read+0x1c2/0x224 > [<ffffffff8007e46a>] up_read+0x1c/0x26 > [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 > [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 > [<ffffffff80004434>] ret_from_exception+0x0/0x64 > irq event stamp: 371 > hardirqs last enabled at (371): [<ffffffff8000d862>] handle_page_fault+0x36/0x3a4 > hardirqs last disabled at (370): [<ffffffff80b4aef6>] irqentry_enter+0x16/0x4c > softirqs last enabled at (180): [<ffffffff80b56566>] __do_softirq+0x57e/0x66e > softirqs last disabled at (173): [<ffffffff8001f288>] __irq_exit_rcu+0x8c/0x14c > ---[ end trace 0000000000000000 ]--- > > Thanks, > Conor. > > git bisect start > # status: waiting for both good and bad commits > # good: [06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5] Linux 6.5-rc1 > git bisect good 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 > # status: waiting for bad commit, 1 good commit known > # bad: [1e25dd7772483f477f79986d956028e9f47f990a] Add linux-next specific files for 20230725 > git bisect bad 1e25dd7772483f477f79986d956028e9f47f990a > # bad: [73002c8a551db94daa4124dbe61a3340999c556e] Merge branch 'master' of git://linuxtv.org/mchehab/media-next.git > git bisect bad 73002c8a551db94daa4124dbe61a3340999c556e > # bad: [c37659958e0ff5aaffae86df9e696638f58cd3a3] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/joel/bmc.git > git bisect bad c37659958e0ff5aaffae86df9e696638f58cd3a3 > # good: [bdd1d82e7d02bd2764a68a5cc54533dfc2ba452a] Merge tag 'io_uring-6.5-2023-07-21' of git://git.kernel.dk/linux > git bisect good bdd1d82e7d02bd2764a68a5cc54533dfc2ba452a > # good: [d7b4fea201483d40b7cb1f522915531c6e6b168b] mm/page_io: convert count_swpout_vm_event() to take in a folio > git bisect good d7b4fea201483d40b7cb1f522915531c6e6b168b > # good: [46dce626e248cc91b0612f7c6c31b15f48899465] Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git > git bisect good 46dce626e248cc91b0612f7c6c31b15f48899465 > # bad: [e3fb201f858b63a7abf71b5bb563923b6424b98a] Merge branch 'mm-nonmm-unstable' into mm-everything > git bisect bad e3fb201f858b63a7abf71b5bb563923b6424b98a > # good: [1e0fb16464b68936b1b901a7b908c37d6f587b7c] arm64: smccc: replace custom COUNT_ARGS() & CONCATENATE() implementations > git bisect good 1e0fb16464b68936b1b901a7b908c37d6f587b7c > # good: [de32a89e11bab2e9c8c881fbbbad84a492d5ce9c] mm: set up vma iterator for vma_iter_prealloc() calls > git bisect good de32a89e11bab2e9c8c881fbbbad84a492d5ce9c > # bad: [add29438034569277ab967199af39fe42a4d858c] mm: handle PUD faults under the VMA lock > git bisect bad add29438034569277ab967199af39fe42a4d858c > # good: [ecc821b0404e19eebf393f7a5a73d80c3faa69e4] maple_tree: reduce resets during store setup > git bisect good ecc821b0404e19eebf393f7a5a73d80c3faa69e4 > # good: [4e9c4f4a2949a2b47917647283799bb5952f2290] mm: remove CONFIG_PER_VMA_LOCK ifdefs > git bisect good 4e9c4f4a2949a2b47917647283799bb5952f2290 > # bad: [9a709e2cca6097f66aaba411bd8758cf43a39eb9] mm: move FAULT_FLAG_VMA_LOCK check from handle_mm_fault() > git bisect bad 9a709e2cca6097f66aaba411bd8758cf43a39eb9 > # bad: [78b696bb953cb0b553e1cf9084a6e09580aa4e2a] mm: allow per-VMA locks on file-backed VMAs > git bisect bad 78b696bb953cb0b553e1cf9084a6e09580aa4e2a > # first bad commit: [78b696bb953cb0b553e1cf9084a6e09580aa4e2a] mm: allow per-VMA locks on file-backed VMAs > > [ 0.000000] Linux version 6.5.0-rc3-00283-g78b696bb953c (conor@wendy) (ClangBuiltLinux clang version 15.0.7 (/home/ > conor/stuff/dev/llvm/clang 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a), ClangBuiltLinux LLD 15.0.7) #1 SMP PREEMPT @666 > [ 0.000000] Machine model: Microchip PolarFire-SoC Icicle Kit > [ 0.000000] SBI specification v1.0 detected > [ 0.000000] SBI implementation ID=0x1 Version=0x10002 > [ 0.000000] SBI TIME extension detected > [ 0.000000] SBI IPI extension detected > [ 0.000000] SBI RFENCE extension detected > [ 0.000000] SBI SRST extension detected > [ 0.000000] earlycon: ns16550a0 at MMIO32 0x0000000020100000 (options '115200n8') > [ 0.000000] printk: bootconsole [ns16550a0] enabled > [ 0.000000] printk: debug: skip boot console de-registration. > [ 0.000000] efi: UEFI not found. > [ 0.000000] OF: reserved mem: 0x00000000bfc00000..0x00000000bfffffff (4096 KiB) nomap non-reusable region@BFC00000 > [ 0.000000] Zone ranges: > [ 0.000000] DMA32 [mem 0x0000000080000000-0x00000000ffffffff] > [ 0.000000] Normal [mem 0x0000000100000000-0x000000107fffffff] > [ 0.000000] Movable zone start for each node > [ 0.000000] Early memory node ranges > [ 0.000000] node 0: [mem 0x0000000080000000-0x00000000bfbfffff] > [ 0.000000] node 0: [mem 0x00000000bfc00000-0x00000000bfffffff] > [ 0.000000] node 0: [mem 0x0000001040000000-0x000000107fffffff] > [ 0.000000] Initmem setup node 0 [mem 0x0000000080000000-0x000000107fffffff] > [ 0.000000] SBI HSM extension detected > [ 0.000000] CPU with hartid=0 is not available > [ 0.000000] riscv: base ISA extensions acdfim > [ 0.000000] riscv: ELF capabilities acdfim > [ 0.000000] percpu: Embedded 30 pages/cpu s84320 r8192 d30368 u122880 > [ 0.000000] Kernel command line: earlycon keep_bootcon root=/dev/mmcblk1p2 rootdelay=10 reboot=cold > [ 0.000000] Dentry cache hash table entries: 262144 (order: 9, 2097152 bytes, linear) > [ 0.000000] Inode-cache hash table entries: 131072 (order: 8, 1048576 bytes, linear) > [ 0.000000] Built 1 zonelists, mobility grouping on. Total pages: 517120 > [ 0.000000] mem auto-init: stack:all(zero), heap alloc:off, heap free:off > [ 0.000000] software IO TLB: area num 4. > [ 0.000000] software IO TLB: mapped [mem 0x00000000bbc00000-0x00000000bfc00000] (64MB) > [ 0.000000] Virtual kernel memory layout: > [ 0.000000] fixmap : 0xffffffc6fea00000 - 0xffffffc6ff000000 (6144 kB) > [ 0.000000] pci io : 0xffffffc6ff000000 - 0xffffffc700000000 ( 16 MB) > [ 0.000000] vmemmap : 0xffffffc700000000 - 0xffffffc800000000 (4096 MB) > [ 0.000000] vmalloc : 0xffffffc800000000 - 0xffffffd800000000 ( 64 GB) > [ 0.000000] modules : 0xffffffff025d4000 - 0xffffffff80000000 (2010 MB) > [ 0.000000] lowmem : 0xffffffd800000000 - 0xffffffe800000000 ( 64 GB) > [ 0.000000] kernel : 0xffffffff80000000 - 0xffffffffffffffff (2047 MB) > [ 0.000000] Memory: 1913560K/2097152K available (11570K kernel code, 5054K rwdata, 4096K rodata, 6069K init, 11226K > bss, 183592K reserved, 0K cma-reserved) > [ 0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=4, Nodes=1 > [ 0.000000] trace event string verifier disabled > [ 0.000000] Running RCU self tests > [ 0.000000] Running RCU synchronous self tests > [ 0.000000] rcu: Preemptible hierarchical RCU implementation. > [ 0.000000] rcu: RCU lockdep checking is enabled. > [ 0.000000] rcu: RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=4. > [ 0.000000] rcu: RCU debug extended QS entry/exit. > [ 0.000000] Trampoline variant of Tasks RCU enabled. > [ 0.000000] Tracing variant of Tasks RCU enabled. > [ 0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies. > [ 0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=4 > [ 0.000000] Running RCU synchronous self tests > [ 0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0 > [ 0.000000] riscv-intc: unable to find hart id for /cpus/cpu@0/interrupt-controller > [ 0.000000] riscv-intc: 64 local interrupts mapped > [ 0.000000] plic: interrupt-controller@c000000: mapped 186 interrupts with 4 handlers for 9 contexts. > [ 0.000000] riscv: providing IPIs using SBI IPI extension > [ 0.000000] rcu: srcu_init: Setting srcu_struct sizes based on contention. > [ 0.000000] clocksource: riscv_clocksource: mask: 0xffffffffffffffff max_cycles: 0x1d854df40, max_idle_ns: 3526361616960 ns > [ 0.000003] sched_clock: 64 bits at 1000kHz, resolution 1000ns, wraps every 2199023255500ns > [ 0.010570] Console: colour dummy device 80x25 > [ 0.015820] printk: console [tty0] enabled > [ 0.020660] Lock dependency validator: Copyright (c) 2006 Red Hat, Inc., Ingo Molnar > [ 0.029527] ... MAX_LOCKDEP_SUBCLASSES: 8 > [ 0.034262] ... MAX_LOCK_DEPTH: 48 > [ 0.039096] ... MAX_LOCKDEP_KEYS: 8192 > [ 0.044121] ... CLASSHASH_SIZE: 4096 > [ 0.049148] ... MAX_LOCKDEP_ENTRIES: 32768 > [ 0.054277] ... MAX_LOCKDEP_CHAINS: 65536 > [ 0.059407] ... CHAINHASH_SIZE: 32768 > [ 0.064539] memory used by lock dependency info: 6493 kB > [ 0.070744] memory used for stack traces: 4224 kB > [ 0.076263] per task-struct memory footprint: 1920 bytes > [ 0.082662] Calibrating delay loop (skipped), value calculated using timer frequency.. 2.00 BogoMIPS (lpj=4000) > [ 0.094225] pid_max: default: 32768 minimum: 301 > [ 0.100802] Mount-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) > [ 0.109469] Mountpoint-cache hash table entries: 4096 (order: 3, 32768 bytes, linear) > [ 0.125003] Running RCU synchronous self tests > [ 0.130214] Running RCU synchronous self tests > [ 0.137709] CPU node for /cpus/cpu@0 exist but the possible cpu range is :0-3 > [ 0.155633] RCU Tasks: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. > [ 0.164714] RCU Tasks Trace: Setting shift to 2 and lim to 1 rcu_task_cb_adjust=1. > [ 0.174340] Running RCU-tasks wait API self tests > [ 0.286157] riscv: ELF compat mode unsupported > [ 0.286208] ASID allocator disabled (0 bits) > [ 0.296532] Callback from call_rcu_tasks_trace() invoked. > [ 0.304124] rcu: Hierarchical SRCU implementation. > [ 0.309791] rcu: Max phase no-delay instances is 1000. > [ 0.321671] EFI services will not be available. > [ 0.329990] smp: Bringing up secondary CPUs ... > [ 0.354947] smp: Brought up 1 node, 4 CPUs > [ 0.365578] devtmpfs: initialized > [ 0.410073] Running RCU synchronous self tests > [ 0.416094] Running RCU synchronous self tests > [ 0.421843] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 7645041785100000 ns > [ 0.433116] futex hash table entries: 1024 (order: 5, 131072 bytes, linear) > [ 0.442918] pinctrl core: initialized pinctrl subsystem > [ 0.456687] NET: Registered PF_NETLINK/PF_ROUTE protocol family > [ 0.468413] DMA: preallocated 256 KiB GFP_KERNEL pool for atomic allocations > [ 0.476749] DMA: preallocated 256 KiB GFP_KERNEL|GFP_DMA32 pool for atomic allocations > [ 0.492183] cpuidle: using governor menu > [ 0.558914] Callback from call_rcu_tasks() invoked. > [ 0.613189] HugeTLB: registered 2.00 MiB page size, pre-allocated 0 pages > [ 0.621137] HugeTLB: 0 KiB vmemmap can be freed for a 2.00 MiB page > [ 0.635532] ACPI: Interpreter disabled. > [ 0.659634] SCSI subsystem initialized > [ 0.667627] usbcore: registered new interface driver usbfs > [ 0.674440] usbcore: registered new interface driver hub > [ 0.680969] usbcore: registered new device driver usb > [ 0.690490] FPGA manager framework > [ 0.703508] vgaarb: loaded > [ 0.708569] clocksource: Switched to clocksource riscv_clocksource > [ 0.723150] pnp: PnP ACPI: disabled > [ 0.809949] NET: Registered PF_INET protocol family > [ 0.818618] IP idents hash table entries: 32768 (order: 6, 262144 bytes, linear) > [ 0.839293] tcp_listen_portaddr_hash hash table entries: 1024 (order: 4, 73728 bytes, linear) > [ 0.850714] Table-perturb hash table entries: 65536 (order: 6, 262144 bytes, linear) > [ 0.859721] TCP established hash table entries: 16384 (order: 5, 131072 bytes, linear) > [ 0.872260] TCP bind hash table entries: 16384 (order: 9, 2359296 bytes, linear) > [ 0.902395] TCP: Hash tables configured (established 16384 bind 16384) > [ 0.911840] UDP hash table entries: 1024 (order: 5, 163840 bytes, linear) > [ 0.921420] UDP-Lite hash table entries: 1024 (order: 5, 163840 bytes, linear) > [ 0.932233] NET: Registered PF_UNIX/PF_LOCAL protocol family > [ 0.943727] RPC: Registered named UNIX socket transport module. > [ 0.950879] RPC: Registered udp transport module. > [ 0.956374] RPC: Registered tcp transport module. > [ 0.961926] RPC: Registered tcp-with-tls transport module. > [ 0.968707] RPC: Registered tcp NFSv4.1 backchannel transport module. > [ 0.976198] PCI: CLS 0 bytes, default 64 > [ 0.985222] Unpacking initramfs... > [ 1.000909] workingset: timestamp_bits=62 max_order=19 bucket_order=0 > [ 1.016047] NFS: Registering the id_resolver key type > [ 1.022604] Key type id_resolver registered > [ 1.027625] Key type id_legacy registered > [ 1.032619] nfs4filelayout_init: NFSv4 File Layout Driver Registering... > [ 1.040698] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering... > [ 1.050868] 9p: Installing v9fs 9p2000 file system support > [ 1.059351] NET: Registered PF_ALG protocol family > [ 1.065759] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 246) > [ 1.074615] io scheduler mq-deadline registered > [ 1.079954] io scheduler kyber registered > [ 1.084855] io scheduler bfq registered > [ 2.691196] String selftests succeeded > [ 2.695696] test_string_helpers: Running tests... > [ 2.735759] microchip-pcie 3000000000.pcie: host bridge /pcie@3000000000 ranges: > [ 2.744646] microchip-pcie 3000000000.pcie: MEM 0x3008000000..0x3087ffffff -> 0x0008000000 > [ 2.754854] microchip-pcie 3000000000.pcie: IB MEM 0x0000000000..0x00ffffffff -> 0x0000000000 > [ 2.793603] microchip-pcie 3000000000.pcie: ECAM at [mem 0x3000000000-0x3007ffffff] for [bus 00-7f] > [ 2.806599] microchip-pcie 3000000000.pcie: PCI host bridge to bus 0000:00 > [ 2.814622] pci_bus 0000:00: root bus resource [bus 00-7f] > [ 2.821060] pci_bus 0000:00: root bus resource [mem 0x3008000000-0x3087ffffff] (bus address [0x08000000-0x87ffffff] > ) > [ 2.833923] pci 0000:00:00.0: [11aa:1556] type 01 class 0x000604 > [ 2.841032] pci 0000:00:00.0: reg 0x10: [mem 0x00000000-0x7fffffff 64bit pref] > [ 2.850230] pci 0000:00:00.0: supports D1 D2 > [ 2.855282] pci 0000:00:00.0: PME# supported from D0 D1 D2 D3hot D3cold > [ 2.918454] pci_bus 0000:01: busn_res: [bus 01-7f] end is updated to 01 > [ 2.926316] pci 0000:00:00.0: BAR 0: no space for [mem size 0x80000000 64bit pref] > [ 2.935124] pci 0000:00:00.0: BAR 0: failed to assign [mem size 0x80000000 64bit pref] > [ 2.944337] pci 0000:00:00.0: BAR 8: assigned [mem 0x3008000000-0x30081fffff] > [ 2.952729] pci 0000:00:00.0: BAR 9: assigned [mem 0x3008200000-0x30083fffff 64bit pref] > [ 2.962291] pci 0000:00:00.0: BAR 7: no space for [io size 0x1000] > [ 2.969658] pci 0000:00:00.0: BAR 7: failed to assign [io size 0x1000] > [ 2.977402] pci 0000:00:00.0: PCI bridge to [bus 01] > [ 2.983258] pci 0000:00:00.0: bridge window [mem 0x3008000000-0x30081fffff] > [ 2.991555] pci 0000:00:00.0: bridge window [mem 0x3008200000-0x30083fffff 64bit pref] > [ 3.012105] CCACHE: 4 banks, 16 ways, sets/bank=512, bytes/block=64 > [ 3.019534] CCACHE: Index of the largest way enabled: 11 > [ 3.553216] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled > [ 3.599227] 20100000.serial: ttyS1 at MMIO 0x20100000 (irq = 53, base_baud = 9375000) is a 16550A > [ 3.610933] printk: console [ttyS1] enabled > [ 3.610933] printk: console [ttyS1] enabled > [ 3.635869] 20102000.serial: ttyS2 at MMIO 0x20102000 (irq = 54, base_baud = 9375000) is a 16550A > [ 3.670527] 20104000.serial: ttyS3 at MMIO 0x20104000 (irq = 55, base_baud = 9375000) is a 16550A > [ 3.706515] 20106000.serial: ttyS0 at MMIO 0x20106000 (irq = 56, base_baud = 9375000) is a 16550A > [ 3.823007] loop: module loaded > [ 3.839186] zram: Added device: zram0 > [ 3.867557] microchip-corespi 20108000.spi: Registered SPI controller 0 > [ 3.887509] microchip-corespi 20109000.spi: Registered SPI controller 1 > [ 5.062117] macb 20110000.ethernet eth0: Cadence GEM rev 0x0107010c at 0x20110000 irq 60 (00:04:a3:bf:d2:70) > [ 6.106111] Freeing initrd memory: 25480K > [ 6.124243] > [ 6.127470] ===================================== > [ 6.137414] WARNING: bad unlock balance detected! > [ 6.147364] 6.5.0-rc3-next-20230725 #1 Not tainted > [ 6.157500] ------------------------------------- > [ 6.167447] modprobe/58 is trying to release lock (&vma->vm_lock->lock) at: > [ 6.182194] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > [ 6.193279] but there are no more locks to release! > [ 6.203590] > [ 6.203590] other info that might help us debug this: > [ 6.217392] 1 lock held by modprobe/58: > [ 6.225516] #0: ffffffff8169daa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x2e > [ 6.243441] > [ 6.243441] stack backtrace: > [ 6.252662] CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 > [ 6.268319] Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) > [ 6.281383] Call Trace: > [ 6.286563] [<ffffffff80006b48>] show_stack+0x2c/0x38 > [ 6.297274] [<ffffffff80b49bb2>] dump_stack_lvl+0x60/0x82 > [ 6.308723] [<ffffffff80b49be8>] dump_stack+0x14/0x1c > [ 6.319417] [<ffffffff80089d5a>] print_unlock_imbalance_bug+0x1cc/0x1d6 > [ 6.333417] [<ffffffff80085e4a>] lock_release+0x236/0x3ae > [ 6.344867] [<ffffffff8007e464>] up_read+0x16/0x26 > [ 6.355013] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > [ 6.366072] [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 > [ 6.378415] [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 > [ 6.389656] [<ffffffff80004434>] ret_from_exception+0x0/0x64 > [ 6.401771] ------------[ cut here ]------------ > [ 6.411655] DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffffffe7c63c1558, owner = 0x1, curr 0xffffffe7c0add600, list empty > [ 6.439789] WARNING: CPU: 3 PID: 58 at kernel/locking/rwsem.c:1348 __up_read+0x1c2/0x224 > [ 6.439840] Modules linked in: > [ 6.439855] CPU: 3 PID: 58 Comm: modprobe Not tainted 6.5.0-rc3-next-20230725 #1 > [ 6.439884] Hardware name: Microchip PolarFire-SoC Icicle Kit (DT) > [ 6.439896] epc : __up_read+0x1c2/0x224 > [ 6.439923] ra : __up_read+0x1c2/0x224 > [ 6.439947] epc : ffffffff8007e636 ra : ffffffff8007e636 sp : ffffffc8002b3df0 > [ 6.439966] gp : ffffffff818ad0f0 tp : ffffffe7c0add600 t0 : ffffffc8002b3ab8 > [ 6.439986] t1 : 0000000000000044 t2 : 5357525f47554245 s0 : ffffffc8002b3e20 > [ 6.440004] s1 : ffffffffffffff00 a0 : b32cfaf25517f300 a1 : b32cfaf25517f300 > [ 6.440023] a2 : b32cfaf25517f300 a3 : c0000000ffffefff a4 : 00000fff00000000 > [ 6.440042] a5 : 0000000000000004 a6 : ffffffff81643e90 a7 : 0000000000000038 > [ 6.440060] s2 : ffffffe7c63c1560 s3 : ffffffff81ae3578 s4 : ffffffe7c63c1558 > [ 6.440079] s5 : ffffffc8002b3ee0 s6 : 0000000000000254 s7 : ffffffe7c63c05a0 > [ 6.440098] s8 : 0000003f97687780 s9 : ffffffffeffffef5 s10: 000000006474e553 > [ 6.440117] s11: 0000000000000000 t3 : ffffffff8259430f t4 : ffffffff8259430f > [ 6.440136] t5 : ffffffff82594310 t6 : ffffffff8259430f > [ 6.440151] status: 0000000200000120 badaddr: 0000000000000000 cause: 0000000000000003 > [ 6.440169] [<ffffffff8007e636>] __up_read+0x1c2/0x224 > [ 6.440201] [<ffffffff8007e46a>] up_read+0x1c/0x26 > [ 6.440229] [<ffffffff8000dcfa>] vma_end_read+0x60/0xb8 > [ 6.440255] [<ffffffff8000d9ca>] handle_page_fault+0x19e/0x3a4 > [ 6.440282] [<ffffffff80b4a18c>] do_page_fault+0x20/0x56 > [ 6.440309] [<ffffffff80004434>] ret_from_exception+0x0/0x64 > [ 6.440339] irq event stamp: 371 > [ 6.440347] hardirqs last enabled at (371): [<ffffffff8000d862>] handle_page_fault+0x36/0x3a4 > [ 6.440377] hardirqs last disabled at (370): [<ffffffff80b4aef6>] irqentry_enter+0x16/0x4c > [ 6.440407] softirqs last enabled at (180): [<ffffffff80b56566>] __do_softirq+0x57e/0x66e > [ 6.440453] softirqs last disabled at (173): [<ffffffff8001f288>] __irq_exit_rcu+0x8c/0x14c > [ 6.440494] ---[ end trace 0000000000000000 ]---
On Tue, Jul 25, 2023 at 07:15:08AM -0700, Suren Baghdasaryan wrote: > On Tue, Jul 25, 2023 at 5:58 AM Conor Dooley <conor.dooley@microchip.com> wrote: > > > > Hey, > > > > On Mon, Jul 24, 2023 at 07:54:02PM +0100, Matthew Wilcox (Oracle) wrote: > > > Remove the TCP layering violation by allowing per-VMA locks on all VMAs. > > > The fault path will immediately fail in handle_mm_fault(). There may be > > > a small performance reduction from this patch as a little unnecessary work > > > will be done on each page fault. See later patches for the improvement. > > > > > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > > > Reviewed-by: Suren Baghdasaryan <surenb@google.com> > > > Cc: Arjun Roy <arjunroy@google.com> > > > Cc: Eric Dumazet <edumazet@google.com> > > > > Unless my bisection has gone awry, this is causing boot failures for me > > in today's linux-next w/ a splat like so. > > This patch requires [1] to work correctly. It follows the rule > introduced in [1] that anyone returning VM_FAULT_RETRY should also do > vma_end_read(). [1] is merged into mm-unstable but has not reached > linux-next yet, it seems. No, it's in linux-next, but you didn't fix riscv ... Andrew, can you add this fix to Suren's patch? "mm: drop per-VMA lock when returning VM_FAULT_RETRY or VM_FAULT_COMPLETED" diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index 046732fcb48c..6115d7514972 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -296,7 +296,8 @@ void handle_page_fault(struct pt_regs *regs) } fault = handle_mm_fault(vma, addr, flags | FAULT_FLAG_VMA_LOCK, regs); - vma_end_read(vma); + if (!(fault & (VM_FAULT_RETRY | VM_FAULT_COMPLETED))) + vma_end_read(vma); if (!(fault & VM_FAULT_RETRY)) { count_vm_vma_lock_event(VMA_LOCK_SUCCESS);
diff --git a/MAINTAINERS b/MAINTAINERS index 220566cd8da8..f5f5134219b4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14874,7 +14874,6 @@ NETWORKING [TCP] M: Eric Dumazet <edumazet@google.com> L: netdev@vger.kernel.org S: Maintained -F: include/linux/net_mm.h F: include/linux/tcp.h F: include/net/tcp.h F: include/trace/events/tcp.h diff --git a/include/linux/net_mm.h b/include/linux/net_mm.h deleted file mode 100644 index b298998bd5a0..000000000000 --- a/include/linux/net_mm.h +++ /dev/null @@ -1,17 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ -#ifdef CONFIG_MMU - -#ifdef CONFIG_INET -extern const struct vm_operations_struct tcp_vm_ops; -static inline bool vma_is_tcp(const struct vm_area_struct *vma) -{ - return vma->vm_ops == &tcp_vm_ops; -} -#else -static inline bool vma_is_tcp(const struct vm_area_struct *vma) -{ - return false; -} -#endif /* CONFIG_INET*/ - -#endif /* CONFIG_MMU */ diff --git a/include/net/tcp.h b/include/net/tcp.h index d17cb8ab4c48..9d1d312c90c2 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -45,7 +45,6 @@ #include <linux/memcontrol.h> #include <linux/bpf-cgroup.h> #include <linux/siphash.h> -#include <linux/net_mm.h> extern struct inet_hashinfo tcp_hashinfo; diff --git a/mm/memory.c b/mm/memory.c index 7ff73a197cce..c7ad754dd8ed 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -77,7 +77,6 @@ #include <linux/ptrace.h> #include <linux/vmalloc.h> #include <linux/sched/sysctl.h> -#include <linux/net_mm.h> #include <trace/events/kmem.h> @@ -5362,6 +5361,11 @@ vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address, goto out; } + if ((flags & FAULT_FLAG_VMA_LOCK) && !vma_is_anonymous(vma)) { + vma_end_read(vma); + return VM_FAULT_RETRY; + } + /* * Enable the memcg OOM handling for faults triggered in user * space. Kernel faults are handled more gracefully. @@ -5533,12 +5537,8 @@ struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, if (!vma) goto inval; - /* Only anonymous and tcp vmas are supported for now */ - if (!vma_is_anonymous(vma) && !vma_is_tcp(vma)) - goto inval; - /* find_mergeable_anon_vma uses adjacent vmas which are not locked */ - if (!vma->anon_vma && !vma_is_tcp(vma)) + if (vma_is_anonymous(vma) && !vma->anon_vma) goto inval; if (!vma_start_read(vma)) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index aca5620cf3ba..f7391d017c4c 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1740,7 +1740,7 @@ void tcp_update_recv_tstamps(struct sk_buff *skb, } #ifdef CONFIG_MMU -const struct vm_operations_struct tcp_vm_ops = { +static const struct vm_operations_struct tcp_vm_ops = { }; int tcp_mmap(struct file *file, struct socket *sock, @@ -2043,13 +2043,10 @@ static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, unsigned long address, bool *mmap_locked) { - struct vm_area_struct *vma = NULL; + struct vm_area_struct *vma = lock_vma_under_rcu(mm, address); -#ifdef CONFIG_PER_VMA_LOCK - vma = lock_vma_under_rcu(mm, address); -#endif if (vma) { - if (!vma_is_tcp(vma)) { + if (vma->vm_ops != &tcp_vm_ops) { vma_end_read(vma); return NULL; } @@ -2059,7 +2056,7 @@ static struct vm_area_struct *find_tcp_vma(struct mm_struct *mm, mmap_read_lock(mm); vma = vma_lookup(mm, address); - if (!vma || !vma_is_tcp(vma)) { + if (!vma || vma->vm_ops != &tcp_vm_ops) { mmap_read_unlock(mm); return NULL; }