Hi Robin, On Wednesday, 14 September 2022 17:54:36 CEST Robin Murphy wrote: > On 2022-09-14 16:01, Lucas De Marchi wrote: > > On Wed, Sep 14, 2022 at 02:40:45PM +0200, Karolina Drobnik wrote: > >> This reverts commit ac9a5d522bb80be50ea84965699e1c8257d745ce. > >> > >> This change introduces a regression on Alder Lake that completely > >> blocks testing. To enable CI and avoid possible circular locking > >> warning, revert the patch. > > > > We are already on rc5. Are iommu authors involved aware of this issue? > > We could do this in our "for CI only" branch, but it's equally important > > that this is fixed for 6.0 > > > > Cc'ing them. > > The lockdep report doesn't make much sense to me - the deadlock cycle > it's reporting doesn't even involve the mutex added by that commit, and > otherwise the lock ordering between the IOMMU bus notifier(s) and > cpu_hotplug_lock has existed for ages. Indeed, that lockdep report is not quite related, but there are other lockdep reports in our CI results that better justify the revert. https://intel-gfx-ci.01.org/tree/drm-tip/TrybotIGT_595/bat-dg2-8/igt@core_hotunplug@xxxxxxxxxxxxxxxxxx ... <7> [181.565177] [IGT] core_hotunplug: unplugging the device <7> [181.565372] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling DC_off <7> [181.565708] i915 0000:03:00.0: [drm:gen9_set_dc_state.part.15 [i915]] Setting DC state from 01 to 00 <7> [181.566060] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_2 <7> [181.566216] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_A <7> [181.566447] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_B <7> [181.566607] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_C <7> [181.566765] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_D <7> [181.570683] intel_gt_set_wedged called from intel_gt_set_wedged_on_fini+0x9/0x30 [i915] <7> [181.659480] i915 0000:03:00.0: [drm:drm_client_release] drm_fb_helper <6> [181.773310] pci 0000:03:00.0: Removing from iommu group 1 <7> [181.774416] [IGT] core_hotunplug: rediscovering the device <6> [181.775800] pci 0000:03:00.0: [8086:56a0] type 00 class 0x030000 <6> [181.775833] pci 0000:03:00.0: reg 0x10: [mem 0x90000000-0x90ffffff 64bit] <6> [181.775852] pci 0000:03:00.0: reg 0x18: [mem 0x4000000000-0x43ffffffff 64bit pref] <6> [181.775886] pci 0000:03:00.0: reg 0x30: [mem 0xffe00000-0xffffffff pref] <6> [181.776058] pci 0000:03:00.0: ASPM: overriding L1 acceptable latency from 0x0 to 0x7 <6> [181.776073] pci 0000:03:00.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff] <6> [181.776209] pci 0000:03:00.0: PME# supported from D0 D3hot <6> [181.776869] pci 0000:03:00.0: vgaarb: setting as boot VGA device <6> [181.776878] pci 0000:03:00.0: vgaarb: bridge control possible <6> [181.776881] pci 0000:03:00.0: vgaarb: VGA device added: decodes=io+mem,owns=io+mem,locks=none <6> [181.777052] pci 0000:03:00.0: Adding to iommu group 1 <4> [181.777164] <4> [181.777169] ====================================================== <4> [181.777176] WARNING: possible circular locking dependency detected <4> [181.777182] 6.0.0-rc5-CI_DRM_12145-g2dc9ea03abff+ #1 Not tainted <4> [181.777189] ------------------------------------------------------ <4> [181.777196] core_hotunplug/1240 is trying to acquire lock: <4> [181.777202] ffff8881029b33b0 (&domain->iova_cookie->mutex){+.+.}-{3:3}, at: iommu_setup_dma_ops+0xd7/0x440 <4> [181.777218] but task is already holding lock: <4> [181.777225] ffff8881010c9e78 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x20/0x50 <4> [181.777242] which lock already depends on the new lock. <4> [181.777250] the existing dependency chain (in reverse order) is: <4> [181.777258] -> #3 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}: <4> [181.777268] lock_acquire+0xd3/0x310 <4> [181.777274] down_read+0x39/0x140 <4> [181.777281] blocking_notifier_call_chain+0x20/0x50 <4> [181.777289] device_add+0x3c1/0x900 <4> [181.777295] platform_device_add+0x108/0x240 <4> [181.777302] coretemp_cpu_online+0xe1/0x15e [coretemp] <4> [181.777310] cpuhp_invoke_callback+0x181/0x8a0 <4> [181.777318] cpuhp_thread_fun+0x188/0x1f0 <4> [181.777325] smpboot_thread_fn+0x1b5/0x260 <4> [181.777332] kthread+0xed/0x120 <4> [181.777337] ret_from_fork+0x1f/0x30 <4> [181.777343] -> #2 (cpuhp_state-up){+.+.}-{0:0}: <4> [181.777352] lock_acquire+0xd3/0x310 <4> [181.777358] cpuhp_thread_fun+0xa6/0x1f0 <4> [181.777364] smpboot_thread_fn+0x1b5/0x260 <4> [181.777370] kthread+0xed/0x120 <4> [181.777375] ret_from_fork+0x1f/0x30 <4> [181.777381] -> #1 (cpu_hotplug_lock){++++}-{0:0}: <4> [181.777390] lock_acquire+0xd3/0x310 <4> [181.777395] __cpuhp_state_add_instance+0x43/0x1c0 <4> [181.777402] iova_domain_init_rcaches+0x199/0x1c0 <4> [181.777409] iommu_setup_dma_ops+0x130/0x440 <4> [181.777415] bus_iommu_probe+0x26a/0x2d0 <4> [181.777422] bus_set_iommu+0x82/0xd0 <4> [181.777428] intel_iommu_init+0xe33/0x1039 <4> [181.777435] pci_iommu_init+0x9/0x31 <4> [181.777442] do_one_initcall+0x53/0x2f0 <4> [181.777448] kernel_init_freeable+0x18f/0x1e1 <4> [181.777455] kernel_init+0x11/0x120 <4> [181.777461] ret_from_fork+0x1f/0x30 <4> [181.777467] -> #0 (&domain->iova_cookie->mutex){+.+.}-{3:3}: <4> [181.777477] validate_chain+0xb3f/0x2000 <4> [181.777484] __lock_acquire+0x5a4/0xb70 <4> [181.777490] lock_acquire+0xd3/0x310 <4> [181.777495] __mutex_lock+0x97/0xf10 <4> [181.777501] iommu_setup_dma_ops+0xd7/0x440 <4> [181.777507] iommu_probe_device+0xa4/0x180 <4> [181.777514] iommu_bus_notifier+0x2d/0x40 <4> [181.777521] notifier_call_chain+0x31/0x90 <4> [181.777528] blocking_notifier_call_chain+0x3a/0x50 <4> [181.777535] device_add+0x3c1/0x900 <4> [181.777541] pci_device_add+0x255/0x580 <4> [181.777548] pci_scan_single_device+0xa6/0xd0 <4> [181.777555] pci_scan_slot+0x7a/0x1b0 <4> [181.777561] pci_scan_child_bus_extend+0x35/0x2a0 <4> [181.777568] pci_scan_bridge_extend+0x588/0x650 <4> [181.777575] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.777582] pci_scan_bridge_extend+0x588/0x650 <4> [181.777589] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.777596] pci_scan_bridge_extend+0x588/0x650 <4> [181.777602] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.777609] pci_rescan_bus+0xc/0x30 <4> [181.777616] rescan_store+0x60/0x90 <4> [181.777622] kernfs_fop_write_iter+0x121/0x1c0 <4> [181.777630] vfs_write+0x34c/0x4e0 <4> [181.777636] ksys_write+0x57/0xd0 <4> [181.777642] do_syscall_64+0x37/0x90 <4> [181.777648] entry_SYSCALL_64_after_hwframe+0x63/0xcd <4> [181.777655] other info that might help us debug this: <4> [181.777664] Chain exists of: &domain->iova_cookie->mutex --> cpuhp_state-up --> &(&priv->bus_notifier)->rwsem <4> [181.777680] Possible unsafe locking scenario: <4> [181.777686] CPU0 CPU1 <4> [181.777691] ---- ---- <4> [181.777696] lock(&(&priv->bus_notifier)->rwsem); <4> [181.777703] lock(cpuhp_state-up); <4> [181.777710] lock(&(&priv->bus_notifier)->rwsem); <4> [181.777719] lock(&domain->iova_cookie->mutex); <4> [181.777725] *** DEADLOCK *** <4> [181.777732] 5 locks held by core_hotunplug/1240: <4> [181.777738] #0: ffff888106e3c430 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x57/0xd0 <4> [181.777752] #1: ffff888118f92688 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xee/0x1c0 <4> [181.777764] #2: ffff8881010952a0 (kn->active#405){.+.+}-{0:0}, at: kernfs_fop_write_iter+0xf7/0x1c0 <4> [181.777778] #3: ffffffff827a48c8 (pci_rescan_remove_lock){+.+.}-{3:3}, at: rescan_store+0x54/0x90 <4> [181.777792] #4: ffff8881010c9e78 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x20/0x50 <4> [181.777807] stack backtrace: <4> [181.777813] CPU: 9 PID: 1240 Comm: core_hotunplug Not tainted 6.0.0-rc5-CI_DRM_12145-g2dc9ea03abff+ #1 <4> [181.777824] Hardware name: Intel Corporation CoffeeLake Client Platform/CoffeeLake S UDIMM RVP, BIOS CNLSFWR1.R00.X220.B00.2103302221 03/30/2021 <4> [181.777837] Call Trace: <4> [181.777840] <TASK> <4> [181.777844] dump_stack_lvl+0x56/0x7f <4> [181.777851] check_noncircular+0x132/0x150 <4> [181.777858] ? validate_chain+0x247/0x2000 <4> [181.777867] validate_chain+0xb3f/0x2000 <4> [181.777876] __lock_acquire+0x5a4/0xb70 <4> [181.777883] lock_acquire+0xd3/0x310 <4> [181.777889] ? iommu_setup_dma_ops+0xd7/0x440 <4> [181.777897] __mutex_lock+0x97/0xf10 <4> [181.777903] ? iommu_setup_dma_ops+0xd7/0x440 <4> [181.777910] ? iommu_setup_dma_ops+0xd7/0x440 <4> [181.777918] ? iommu_setup_dma_ops+0xd7/0x440 <4> [181.777924] iommu_setup_dma_ops+0xd7/0x440 <4> [181.777931] ? __mutex_unlock_slowpath+0x3e/0x2b0 <4> [181.777939] iommu_probe_device+0xa4/0x180 <4> [181.777947] iommu_bus_notifier+0x2d/0x40 <4> [181.777953] notifier_call_chain+0x31/0x90 <4> [181.777961] blocking_notifier_call_chain+0x3a/0x50 <4> [181.777968] device_add+0x3c1/0x900 <4> [181.777974] ? _raw_read_unlock+0x24/0x40 <4> [181.777980] ? region_intersects+0x95/0xb0 <4> [181.777988] pci_device_add+0x255/0x580 <4> [181.777994] ? pci_setup_device.cold.56+0x318/0x5b6 <4> [181.778003] pci_scan_single_device+0xa6/0xd0 <4> [181.778010] pci_scan_slot+0x7a/0x1b0 <4> [181.778017] pci_scan_child_bus_extend+0x35/0x2a0 <4> [181.778026] pci_scan_bridge_extend+0x588/0x650 <4> [181.778034] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.778042] pci_scan_bridge_extend+0x588/0x650 <4> [181.778051] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.778059] pci_scan_bridge_extend+0x588/0x650 <4> [181.778068] pci_scan_child_bus_extend+0xd7/0x2a0 <4> [181.778076] pci_rescan_bus+0xc/0x30 <4> [181.778082] rescan_store+0x60/0x90 <4> [181.778089] kernfs_fop_write_iter+0x121/0x1c0 <4> [181.778096] vfs_write+0x34c/0x4e0 <4> [181.778104] ksys_write+0x57/0xd0 <4> [181.778111] do_syscall_64+0x37/0x90 <4> [181.778117] entry_SYSCALL_64_after_hwframe+0x63/0xcd <4> [181.778123] RIP: 0033:0x7f43eb46e2f7 <4> [181.778129] Code: 75 05 48 83 c4 58 c3 e8 f7 33 ff ff 0f 1f 80 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24 <4> [181.778148] RSP: 002b:00007ffe001a12a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 <4> [181.778158] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f43eb46e2f7 <4> [181.778166] RDX: 0000000000000001 RSI: 0000559c8480518a RDI: 0000000000000005 <4> [181.778173] RBP: 0000559c8480518a R08: 0000000000000000 R09: 0000000000000000 <4> [181.778181] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 <4> [181.778189] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 <4> [181.778200] </TASK> ... The same test on kernel with the revert applied (https://intel-gfx-ci.01.org/tree/drm-tip/TrybotIGT_598/bat-dg2-8/igt@core_hotunplug@xxxxxxxxxxxxxxxxxx): ... <7> [172.263693] [IGT] core_hotunplug: unplugging the device <7> [172.263862] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling DC_off <7> [172.264185] i915 0000:03:00.0: [drm:gen9_set_dc_state.part.15 [i915]] Setting DC state from 01 to 00 <7> [172.264535] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_2 <7> [172.264707] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_A <7> [172.264931] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_B <7> [172.265098] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_C <7> [172.265264] i915 0000:03:00.0: [drm:intel_power_well_enable [i915]] enabling PW_D <7> [172.268842] intel_gt_set_wedged called from intel_gt_set_wedged_on_fini+0x9/0x30 [i915] <7> [172.346115] i915 0000:03:00.0: [drm:drm_client_release] drm_fb_helper <6> [172.467208] pci 0000:03:00.0: Removing from iommu group 1 <7> [172.468877] [IGT] core_hotunplug: rediscovering the device <6> [172.470464] pci 0000:03:00.0: [8086:56a0] type 00 class 0x030000 <6> [172.470504] pci 0000:03:00.0: reg 0x10: [mem 0x90000000-0x90ffffff 64bit] <6> [172.470527] pci 0000:03:00.0: reg 0x18: [mem 0x4000000000-0x43ffffffff 64bit pref] <6> [172.470567] pci 0000:03:00.0: reg 0x30: [mem 0xffe00000-0xffffffff pref] <6> [172.470821] pci 0000:03:00.0: ASPM: overriding L1 acceptable latency from 0x0 to 0x7 <6> [172.470840] pci 0000:03:00.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff] <6> [172.471014] pci 0000:03:00.0: PME# supported from D0 D3hot <6> [172.471890] pci 0000:03:00.0: vgaarb: setting as boot VGA device <6> [172.471903] pci 0000:03:00.0: vgaarb: bridge control possible <6> [172.471906] pci 0000:03:00.0: vgaarb: VGA device added: decodes=io+mem,owns=io+mem,locks=none <6> [172.472135] pci 0000:03:00.0: Adding to iommu group 1 <6> [172.472911] pci 0000:03:00.0: BAR 2: assigned [mem 0x4000000000-0x43ffffffff 64bit pref] <6> [172.472932] pci 0000:03:00.0: BAR 0: assigned [mem 0x90000000-0x90ffffff 64bit] <7> [172.474922] i915 0000:03:00.0: [drm:i915_driver_probe [i915]] WOPCM: 2048K ... For completeness of the picture, here is a list of kernel commits present in TrybotIGT_598 and not present in TrybotIGT_595: a7c48a0ab87ae52c087d663e83e56b8225ac4cce drm/panel: simple: Fix innolux_g121i1_l01 bus_format 521a547ced6477c54b4b0cc206000406c221b4d6 Linux 6.0-rc6 c989a62484ad75e0a06f2ffe67886e7cb6d41659 drm/gma500: Call acpi_video_register_backlight() a7b98d4dfe68654641d56cdc7eace2c36be93a2d drm/gma500: Don't register backlight when another backlight should be used fbf3093466d05461e3f307ffe6b1150daa4b065b drm/gma500: Use backlight_get_brightness() to get the brightness dec4ddbe1d4a4414092309611cc97e6b9dc7ec3f drm/gma500: Change registered backlight device type to raw/native 1f90b1232773249d924868bec3c31525a69fd482 drm/gma500: Refactor backlight support (v2) 9bd3f728223ebcfef8e9d087bdd142f0e388215d io_uring/opdef: rename SENDZC_NOTIF to SEND_ZC e3366e0234971a09f0e16f0e6fa16f4cbae45e47 io_uring/net: fix zc fixed buf lifetime e10ea7b9b90219da305a16b3c1252169715a807b drm: panel-orientation-quirks: Add quirk for Aya Neo Air 74f481f187ce8b37ec5143cee19147da5243009c drm/gma500: Remove unnecessary suspend/resume wrappers 672c473576ca5c9f5a40ac848c938e6898a5aac8 drm/gma500: Rewrite power management code d35a4bf66079b92e232ac85b08f19312be9b7eca drm/gma500: Remove a couple of not useful function wrappers f3b173e9094f5b02fb92d641e3e71fee0bcda73a drm/gma500: Remove never set dev_priv->rpm_enabled flag 49da26d7b418cfc99ad2473a2e3dee2e08c5ba4a drm/gma500: Remove runtime_allowed dead code in psb_unlocked_ioctl() 9b6a16575ebf23a98a9ff84aedde9f3b25731714 drm/gma500: Fix (vblank) IRQs not working after suspend/resume 2830ca9e5b98bee82f1d1e284ce23fe7fb244ea8 drm/vboxvideo: fix repeated words in comments 770e19076065e079a32f33eb11be2057c87f1cde drm: panel-orientation-quirks: Add quirk for Anbernic Win600 8401bd361f5991ccfe9377e502fa37203ad70320 drm/plane-helper: Add a drm_plane_helper_atomic_check() helper 01f0ce3e859619ea84104d668a87ace924bd12df drm/i915/guc: Fix release build bug in 'remove log size module parameters' bc79ef6d5a223ea59acf874f0493b79c835b17d4 Revert "iommu/dma: Fix race condition during iova_domain initialization" 835a4d18353492577093eff7cb6fa866f6e7014f drm/i915/rps: Freq caps for MTL 1551b9164f6194ffee78935d1ff515f697619483 drm/i915/mtl: PERF_LIMIT_REASONS changes for MTL fe5979665f6408092ff6072dc894b74a192cbb53 drm/i915/debugfs: Add perf_limit_reasons in debugfs f569ae759472fbe1f6fdddc7398360d43fdcc199 drm/i915: Handle all GTs on driver (un)load paths 4b3823ff7fa5bd000aa73384ec1f611980d00855 drm/i915: Make GEM suspend all GTs e23a40040819a7a3fcda3c6cedaeff80ad20c231 drm/i915: Make GEM resume all engines 78a033433a5ae4fee85511ee075bc9a48312c79e drm/i915/gt: Cleanup partial engine discovery failures e4dc45b1848bc6bcac31eb1b4ccdd7f6718b3c86 drm/sched: Use parent fence instead of finished b96fb1e724ae6839d5bffcf42dd3503db7cc7df5 dma-buf: dma_fence_wait must enable signaling d62c43a953ce02d54521ec06217d0c2ed6d489af dma-buf: Enable signaling on fence for selftests c85d00d4fd8b98ea4d16817f397a4de5e177afd6 dma-buf: set signaling bit for the stub fence 6ad9aa476ce23be45de9dcb03edcdbfdf6117c25 dma-buf: Remove the signaled bit status check fc7222c3a9f56271fba02aabbfbae999042f1679 io_uring/msg_ring: check file type before putting c4fa368466cc1b60bb92f867741488930ddd6034 blk-lib: fix blkdev_issue_secure_erase 805ce8614958c925877ba6b6dc26cdf9f8800474 parisc: Allow CONFIG_64BIT with ARCH=parisc e359b70cc1c51138e166bd4a560e5c5995369a99 parisc: remove obsolete manual allocation aligning in iosapic c297561bc98ad0f2a37ce0178ee3ba89ab586d70 pinctrl: ocelot: Fix interrupt controller 09eed5a1ed3c752892663976837eb4244c2f1984 gpio: mt7621: Make the irqchip immutable 8af8aed97bebe8b26a340da5236e277c3d84a8ec cifs: update internal module number 621a41ae0834cec9cab312d600d2b9de41dc6eac cifs: add missing spinlock around tcon refcount bedc8f76b3539ac4f952114b316bcc2251e808ce cifs: always initialize struct msghdr smb_msg completely 17d3df38dc5f4cec9b0ac6eb79c1859b6e2693a4 cifs: don't send down the destination address to sendmsg for a SOCK_STREAM 56f99b8d06ef1ed1c9730948f9f05ac2b930a20b block: blk_queue_enter() / __bio_queue_enter() must return -EAGAIN for nowait de11663b75b0a8f1cfeb00d3b4acec9bd5a49cad dt-bindings: pinctrl: qcom: drop non-working codeaurora.org emails 969d373228f6624de87aa0982d89a756e8e77471 dt-bindings: power: qcom,rpmpd: drop non-working codeaurora.org emails 94e9bc73d85aa6ecfe249e985ff57abe0ab35f34 gpio: ixp4xx: Make irqchip immutable 1660c679d6d4779fbce937d0c9dc2af56e66e62d MAINTAINERS: Update HiSilicon GPIO Driver maintainer 62bb0647b14646fa6c9aa25ecdf67ad18f13523c io_uring/rw: fix error'ed retry return values da3b1c294d470b2cf3c7046cc9e0d5c66f0a6c65 dt-bindings: apple,aic: Fix required item "apple,fiq-index" in affinity description 95363747a6f39e88a3052fcf6ce6237769495ce0 tools/include/uapi: Fix <asm/errno.h> for parisc and xtensa 4b9d1bc7911c9d9159c4881455c584cde99fbb19 Input: hp_sdc: fix spelling typo in comment 38238be4e881a5d0abbe4872b4cd6ed790be06c8 parisc: ccio-dma: Add missing iounmap in error path in ccio_probe() bfbfb6182ad1d7d184b16f25165faad879147f79 nfsd_splice_actor(): handle compound pages 7500a99281dfed2d4a84771c933bcb9e17af279b cifs: revalidate mapping when doing direct writes 00801cd92d91e94aa04d687f9bb9a9104e7c3d46 NFSD: fix regression with setting ACLs. 13bd9014180425f5a35eaf3735971d582c299292 Revert "SUNRPC: Remove unreachable error condition" d7a5118635e725d195843bda80cc5c964d93ef31 NFSv4.2: Update mode bits after ALLOCATE and DEALLOCATE 12ef2508f33db1654de2f22f75dd868141b8b305 dt-bindings: interconnect: fsl,imx8m-noc: drop Leonard Crestez 279c12df8d2efb28def9d037f288cbfb97c30fe2 gpio: mpc8xxx: Fix support for IRQ_TYPE_LEVEL_LOW flow_type in mpc85xx f0880e2cb7e1f8039a048fdd01ce45ab77247221 Drivers: hv: Never allocate anything besides framebuffer from framebuffer memory region 2a8a8afba0c3053d0ea8686182f6b2104293037e Drivers: hv: Always reserve framebuffer region for Gen1 VMs 8409fe92d88c332923130149fe209d1c882b286e PCI: Move PCI_VENDOR_ID_MICROSOFT/PCI_DEVICE_ID_HYPERV_VIDEO definitions to pci_ids.h 2258954234db7530e9d86bb32cd6ad54485ff926 tools: hv: kvp: remove unnecessary (void*) conversions 676576d164b34a98589a9efee85f57240c07fef3 Drivers: hv: remove duplicate word in a comment 2a9d683b48c8a87e61a4215792d44c90bcbbb536 NFSv4: Turn off open-by-filehandle and NFS re-export for NFSv4.0 17814819ac9829a437e06fbb5c7056a1f4f893da SUNRPC: Fix call completion races with call_decode() 76648c867c6c03b8a468d9c9222025873ecc613d pinctrl: sunxi: Fix name for A100 R_PIO 40bfe7a86d84cf08ac6a8fe2f0c8bf7a43edd110 of/device: Fix up of_dma_configure_id() stub b871656aa4f54e04207f62bdd0d7572be1d86b36 pinctrl: rockchip: Enhance support for IRQ_TYPE_EDGE_BOTH 48ec73395887694f13c9452b4dcfb43710451757 pinctrl: qcom: sc8180x: Fix wrong pin numbers 6124cec530c7d8faab96d340ab2df5161e5d1c8a pinctrl: qcom: sc8180x: Fix gpio_wakeirq_map c6a43fb3487f7e040170e60cdb9b030c669e9cf5 MAINTAINERS: Update email of Neil Armstrong 2f945a792f67815abca26fa8a5e863ccf3fa1181 of: fdt: fix off-by-one error in unflatten_dt_nodes() f15f39fabed2248311607445ddfa6dba63abebb9 tools: hv: Remove an extraneous "the" f1f63cbb705dc38826369496c6fc12c1b8db1324 drm/hyperv: Fix an error handling path in hyperv_vmbus_probe() Thanks, Janusz > Has lockdep somehow got multiple > different and unrelated bus notifiers mixed up, maybe? > > FWIW nobody else has reported anything, and that mutex addresses a > real-world concurrency issue, so I'm not convinced a revert is > appropriate without at least a much clearer justification. > > Robin. > > > thanks > > Lucas De Marchi > > > >> > >> kernel log: > >> > >> ====================================================== > >> WARNING: possible circular locking dependency detected > >> 6.0.0-rc5-CI_DRM_12132-g6c93e979e542+ #1 Not tainted > >> ------------------------------------------------------ > >> cpuhp/0/15 is trying to acquire lock: > >> ffff8881013df278 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}, at: > >> blocking_notifier_call_chain+0x20/0x50 > >> but task is already holding lock: > >> ffffffff826490c0 (cpuhp_state-up){+.+.}-{0:0}, at: > >> cpuhp_thread_fun+0x48/0x1f0 > >> which lock already depends on the new loc > >> the existing dependency chain (in reverse order) is: > >> -> #3 (cpuhp_state-up){+.+.}-{0:0}: > >> lock_acquire+0xd3/0x310 > >> cpuhp_thread_fun+0xa6/0x1f0 > >> smpboot_thread_fn+0x1b5/0x260 > >> kthread+0xed/0x120 > >> ret_from_fork+0x1f/0x30 > >> -> #2 (cpu_hotplug_lock){++++}-{0:0}: > >> lock_acquire+0xd3/0x310 > >> __cpuhp_state_add_instance+0x43/0x1c0 > >> iova_domain_init_rcaches+0x199/0x1c0 > >> iommu_setup_dma_ops+0x130/0x440 > >> bus_iommu_probe+0x26a/0x2d0 > >> bus_set_iommu+0x82/0xd0 > >> intel_iommu_init+0xe33/0x1039 > >> pci_iommu_init+0x9/0x31 > >> do_one_initcall+0x53/0x2f0 > >> kernel_init_freeable+0x18f/0x1e1 > >> kernel_init+0x11/0x120 > >> ret_from_fork+0x1f/0x30 > >> -> #1 (&domain->iova_cookie->mutex){+.+.}-{3:3}: > >> lock_acquire+0xd3/0x310 > >> __mutex_lock+0x97/0xf10 > >> iommu_setup_dma_ops+0xd7/0x440 > >> iommu_probe_device+0xa4/0x180 > >> iommu_bus_notifier+0x2d/0x40 > >> notifier_call_chain+0x31/0x90 > >> blocking_notifier_call_chain+0x3a/0x50 > >> device_add+0x3c1/0x900 > >> pci_device_add+0x255/0x580 > >> pci_scan_single_device+0xa6/0xd0 > >> pci_scan_slot+0x7a/0x1b0 > >> pci_scan_child_bus_extend+0x35/0x2a0 > >> vmd_probe+0x5cd/0x970 > >> pci_device_probe+0x95/0x110 > >> really_probe+0xd6/0x350 > >> __driver_probe_device+0x73/0x170 > >> driver_probe_device+0x1a/0x90 > >> __driver_attach+0xbc/0x190 > >> bus_for_each_dev+0x72/0xc0 > >> bus_add_driver+0x1bb/0x210 > >> driver_register+0x66/0xc0 > >> do_one_initcall+0x53/0x2f0 > >> kernel_init_freeable+0x18f/0x1e1 > >> kernel_init+0x11/0x120 > >> ret_from_fork+0x1f/0x30 > >> -> #0 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}: > >> validate_chain+0xb3f/0x2000 > >> __lock_acquire+0x5a4/0xb70 > >> lock_acquire+0xd3/0x310 > >> down_read+0x39/0x140 > >> blocking_notifier_call_chain+0x20/0x50 > >> device_add+0x3c1/0x900 > >> platform_device_add+0x108/0x240 > >> coretemp_cpu_online+0xe1/0x15e [coretemp] > >> cpuhp_invoke_callback+0x181/0x8a0 > >> cpuhp_thread_fun+0x188/0x1f0 > >> smpboot_thread_fn+0x1b5/0x260 > >> kthread+0xed/0x120 > >> ret_from_fork+0x1f/0x30 > >> other info that might help us debug thi > >> Chain exists of &(&priv->bus_notifier)->rwsem --> > >> cpu_hotplug_lock --> cpuhp_state- > >> Possible unsafe locking scenari > >> CPU0 CPU1 > >> ---- ---- > >> lock(cpuhp_state-up); > >> lock(cpu_hotplug_lock); > >> lock(cpuhp_state-up); > >> lock(&(&priv->bus_notifier)->rwsem); > >> *** DEADLOCK * > >> 2 locks held by cpuhp/0/15: > >> #0: ffffffff82648f10 (cpu_hotplug_lock){++++}-{0:0}, at: > >> cpuhp_thread_fun+0x48/0x1f0 > >> #1: ffffffff826490c0 (cpuhp_state-up){+.+.}-{0:0}, at: > >> cpuhp_thread_fun+0x48/0x1f0 > >> stack backtrace: > >> CPU: 0 PID: 15 Comm: cpuhp/0 Not tainted > >> 6.0.0-rc5-CI_DRM_12132-g6c93e979e542+ #1 > >> Hardware name: Intel Corporation Alder Lake Client > >> Platform/AlderLake-P DDR4 RVP, BIOS ADLPFWI1.R00.3135.A00.2203251419 > >> 03/25/2022 > >> Call Trace: > >> <TASK> > >> dump_stack_lvl+0x56/0x7f > >> check_noncircular+0x132/0x150 > >> validate_chain+0xb3f/0x2000 > >> __lock_acquire+0x5a4/0xb70 > >> lock_acquire+0xd3/0x310 > >> ? blocking_notifier_call_chain+0x20/0x50 > >> down_read+0x39/0x140 > >> ? blocking_notifier_call_chain+0x20/0x50 > >> blocking_notifier_call_chain+0x20/0x50 > >> device_add+0x3c1/0x900 > >> ? dev_set_name+0x4e/0x70 > >> platform_device_add+0x108/0x240 > >> coretemp_cpu_online+0xe1/0x15e [coretemp] > >> ? create_core_data+0x550/0x550 [coretemp] > >> cpuhp_invoke_callback+0x181/0x8a0 > >> cpuhp_thread_fun+0x188/0x1f0 > >> ? smpboot_thread_fn+0x1e/0x260 > >> smpboot_thread_fn+0x1b5/0x260 > >> ? sort_range+0x20/0x20 > >> kthread+0xed/0x120 > >> ? kthread_complete_and_exit+0x20/0x20 > >> ret_from_fork+0x1f/0x30 > >> </TASK> > >> > >> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/6641 > >> > >> Signed-off-by: Karolina Drobnik <karolina.drobnik@xxxxxxxxx> > >> Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> > >> --- > >> drivers/iommu/dma-iommu.c | 17 ++++------------- > >> 1 file changed, 4 insertions(+), 13 deletions(-) > >> > >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > >> index 17dd683b2fce..9616b473e4c7 100644 > >> --- a/drivers/iommu/dma-iommu.c > >> +++ b/drivers/iommu/dma-iommu.c > >> @@ -65,7 +65,6 @@ struct iommu_dma_cookie { > >> > >> /* Domain for flush queue callback; NULL if flush queue not in use */ > >> struct iommu_domain *fq_domain; > >> - struct mutex mutex; > >> }; > >> > >> static DEFINE_STATIC_KEY_FALSE(iommu_deferred_attach_enabled); > >> @@ -312,7 +311,6 @@ int iommu_get_dma_cookie(struct iommu_domain *domain) > >> if (!domain->iova_cookie) > >> return -ENOMEM; > >> > >> - mutex_init(&domain->iova_cookie->mutex); > >> return 0; > >> } > >> > >> @@ -563,33 +561,26 @@ static int iommu_dma_init_domain(struct > >> iommu_domain *domain, dma_addr_t base, > >> } > >> > >> /* start_pfn is always nonzero for an already-initialised domain */ > >> - mutex_lock(&cookie->mutex); > >> if (iovad->start_pfn) { > >> if (1UL << order != iovad->granule || > >> base_pfn != iovad->start_pfn) { > >> pr_warn("Incompatible range for DMA domain\n"); > >> - ret = -EFAULT; > >> - goto done_unlock; > >> + return -EFAULT; > >> } > >> > >> - ret = 0; > >> - goto done_unlock; > >> + return 0; > >> } > >> > >> init_iova_domain(iovad, 1UL << order, base_pfn); > >> ret = iova_domain_init_rcaches(iovad); > >> if (ret) > >> - goto done_unlock; > >> + return ret; > >> > >> /* If the FQ fails we can simply fall back to strict mode */ > >> if (domain->type == IOMMU_DOMAIN_DMA_FQ && iommu_dma_init_fq(domain)) > >> domain->type = IOMMU_DOMAIN_DMA; > >> > >> - ret = iova_reserve_iommu_regions(dev, domain); > >> - > >> -done_unlock: > >> - mutex_unlock(&cookie->mutex); > >> - return ret; > >> + return iova_reserve_iommu_regions(dev, domain); > >> } > >> > >> /** > >> >
