3e817471a3
Some machines require ACPI for runtime resume, and ACPI is quite kmalloc happy. We cannot handle kmalloc from inside the vm->mutex, as they are used by the shrinker, and so we must ensure the global runtime-pm is awake prior to unbinding to avoid the potential inversion. <4> [57.121748] ====================================================== <4> [57.121750] WARNING: possible circular locking dependency detected <4> [57.121753] 5.4.0-rc8-CI-CI_DRM_7466+ #1 Tainted: G U <4> [57.121754] ------------------------------------------------------ <4> [57.121756] i915_pm_rpm/1105 is trying to acquire lock: <4> [57.121758] ffffffff82263a40 (fs_reclaim){+.+.}, at: fs_reclaim_acquire.part.117+0x0/0x30 <4> [57.121766] but task is already holding lock: <4> [57.121768] ffff888475a593c0 (&vm->mutex){+.+.}, at: i915_vma_unbind+0x21/0x50 [i915] <4> [57.121868] which lock already depends on the new lock. <4> [57.121869] the existing dependency chain (in reverse order) is: <4> [57.121871] -> #1 (&vm->mutex){+.+.}: <4> [57.121951] i915_gem_shrinker_taints_mutex+0xa2/0xd0 [i915] <4> [57.122028] i915_address_space_init+0xa9/0x170 [i915] <4> [57.122104] i915_ggtt_init_hw+0x47/0x130 [i915] <4> [57.122150] i915_driver_probe+0xbb4/0x15f0 [i915] <4> [57.122197] i915_pci_probe+0x43/0x1c0 [i915] <4> [57.122202] pci_device_probe+0x9e/0x120 <4> [57.122206] really_probe+0xea/0x420 <4> [57.122209] driver_probe_device+0x10b/0x120 <4> [57.122212] device_driver_attach+0x4a/0x50 <4> [57.122214] __driver_attach+0x97/0x130 <4> [57.122217] bus_for_each_dev+0x74/0xc0 <4> [57.122220] bus_add_driver+0x142/0x220 <4> [57.122222] driver_register+0x56/0xf0 <4> [57.122226] do_one_initcall+0x58/0x2ff <4> [57.122230] do_init_module+0x56/0x1f8 <4> [57.122233] load_module+0x243e/0x29f0 <4> [57.122236] __do_sys_finit_module+0xe9/0x110 <4> [57.122239] do_syscall_64+0x4f/0x210 <4> [57.122242] entry_SYSCALL_64_after_hwframe+0x49/0xbe <4> [57.122244] -> #0 (fs_reclaim){+.+.}: <4> [57.122249] __lock_acquire+0x1328/0x15d0 <4> [57.122251] lock_acquire+0xa7/0x1c0 <4> [57.122254] fs_reclaim_acquire.part.117+0x24/0x30 <4> [57.122257] __kmalloc+0x48/0x320 <4> [57.122261] acpi_ns_internalize_name+0x44/0x9b <4> [57.122264] acpi_ns_get_node_unlocked+0x6b/0xd3 <4> [57.122267] acpi_ns_get_node+0x3b/0x50 <4> [57.122271] acpi_get_handle+0x8a/0xb4 <4> [57.122274] acpi_has_method+0x1c/0x40 <4> [57.122278] acpi_pci_set_power_state+0x40/0xe0 <4> [57.122281] pci_platform_power_transition+0x3e/0x90 <4> [57.122284] pci_set_power_state+0x83/0xf0 <4> [57.122287] pci_restore_standard_config+0x22/0x40 <4> [57.122289] pci_pm_runtime_resume+0x23/0xc0 <4> [57.122293] __rpm_callback+0xb1/0x110 <4> [57.122296] rpm_callback+0x1a/0x70 <4> [57.122299] rpm_resume+0x50e/0x790 <4> [57.122302] __pm_runtime_resume+0x42/0x80 <4> [57.122357] __intel_runtime_pm_get+0x15/0x60 [i915] <4> [57.122435] ggtt_unbind_vma+0x24/0x60 [i915] <4> [57.122514] __i915_vma_unbind.part.39+0xb5/0x500 [i915] <4> [57.122593] i915_vma_unbind+0x2d/0x50 [i915] <4> [57.122668] i915_gem_object_unbind+0x11c/0x260 [i915] <4> [57.122740] i915_gem_object_set_cache_level+0x32/0x90 [i915] <4> [57.122810] i915_gem_set_caching_ioctl+0x1f7/0x2f0 [i915] <4> [57.122815] drm_ioctl_kernel+0xa7/0xf0 <4> [57.122818] drm_ioctl+0x2e1/0x390 <4> [57.122822] do_vfs_ioctl+0xa0/0x6f0 <4> [57.122825] ksys_ioctl+0x35/0x60 <4> [57.122828] __x64_sys_ioctl+0x11/0x20 <4> [57.122830] do_syscall_64+0x4f/0x210 <4> [57.122833] entry_SYSCALL_64_after_hwframe+0x49/0xbe Closes: https://gitlab.freedesktop.org/drm/intel/issues/711 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191203101347.2836057-1-chris@chris-wilson.co.uk
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.