# Some of the tools (perf) use same make variables # as in kernel build. export srctree= export objtree= include scripts/Makefile.include help: @echo 'Possible targets:' @echo '' @echo ' acpi - ACPI tools' @echo ' cgroup - cgroup tools' @echo ' cpupower - a tool for all things x86 CPU power' @echo ' firewire - the userspace part of nosy, an IEEE-1394 traffic sniffer' @echo ' freefall - laptop accelerometer program for disk protection' @echo ' gpio - GPIO tools' @echo ' hv - tools used when in Hyper-V clients' @echo ' iio - IIO tools' @echo ' kvm_stat - top-like utility for displaying kvm statistics' @echo ' leds - LEDs tools' @echo ' lguest - a minimal 32-bit x86 hypervisor' @echo ' net - misc networking tools' @echo ' perf - Linux performance measurement and analysis tool' @echo ' selftests - various kernel selftests' @echo ' spi - spi tools' @echo ' objtool - an ELF object analysis tool' @echo ' tmon - thermal monitoring and tuning tool' @echo ' turbostat - Intel CPU idle stats and freq reporting tool' @echo ' usb - USB testing tools' @echo ' virtio - vhost test module' @echo ' vm - misc vm tools' @echo ' x86_energy_perf_policy - Intel energy policy tool' @echo '' @echo 'You can do:' @echo ' $$ make -C tools/ _install' @echo '' @echo ' from the kernel command line to build and install one of' @echo ' the tools above' @echo '' @echo ' $$ make tools/all' @echo '' @echo ' builds all tools.' @echo '' @echo ' $$ make tools/install' @echo '' @echo ' installs all tools.' @echo '' @echo 'Cleaning targets:' @echo '' @echo ' all of the above with the "_clean" string appended cleans' @echo ' the respective build directory.' @echo ' clean: a summary clean target to clean _all_ folders' acpi: FORCE $(call descend,power/$@) cpupower: FORCE $(call descend,power/$@) cgroup firewire hv guest spi usb virtio vm net iio gpio objtool leds: FORCE $(call descend,$@) liblockdep: FORCE $(call descend,lib/lockdep) libapi: FORCE $(call descend,lib/api) # The perf build does not follow the descend function setup, # invoking it via it's own make rule. PERF_O = $(if $(O),$(O)/tools/perf,) perf: FORCE $(Q)mkdir -p $(PERF_O) . $(Q)$(MAKE) --no-print-directory -C perf O=$(PERF_O) subdir= selftests: FORCE $(call descend,testing/$@) turbostat x86_energy_perf_policy: FORCE $(call descend,power/x86/$@) tmon: FORCE $(call descend,thermal/$@) freefall: FORCE $(call descend,laptop/$@) all: acpi cgroup cpupower gpio hv firewire lguest \ perf selftests turbostat usb \ virtio vm net x86_energy_perf_policy \ tmon freefall objtool acpi_install: $(call descend,power/$(@:_install=),install) cpupower_install: $(call descend,power/$(@:_install=),install) cgroup_install firewire_install gpio_install hv_install lguest_install perf_install usb_install virtio_install vm_install net_install objtool_install: $(call descend,$(@:_install=),install) selftests_install: $(call descend,testing/$(@:_install=),install) turbostat_install x86_energy_perf_policy_install: $(call descend,power/x86/$(@:_install=),install) tmon_install: $(call descend,thermal/$(@:_install=),install) freefall_install: $(call descend,laptop/$(@:_install=),install) kvm_stat_install: $(call descend,kvm/$(@:_install=),install) install: acpi_install cgroup_install cpupower_install gpio_install \ hv_install firewire_install lguest_install \ perf_install selftests_install turbostat_install usb_install \ virtio_install vm_install net_install x86_energy_perf_policy_install \ tmon_install freefall_install objtool_install kvm_stat_install acpi_clean: $(call descend,power/acpi,clean) cpupower_clean: $(call descend,power/cpupower,clean) cgroup_clean hv_clean firewire_clean lguest_clean spi_clean usb_clean virtio_clean vm_clean net_clean iio_clean gpio_clean objtool_clean leds_clean: $(call descend,$(@:_clean=),clean) liblockdep_clean: $(call descend,lib/lockdep,clean) libapi_clean: $(call descend,lib/api,clean) libbpf_clean: $(call descend,lib/bpf,clean) libsubcmd_clean: $(call descend,lib/subcmd,clean) perf_clean: $(Q)mkdir -p $(PERF_O) . $(Q)$(MAKE) --no-print-directory -C perf O=$(PERF_O) subdir= clean selftests_clean: $(call descend,testing/$(@:_clean=),clean) turbostat_clean x86_energy_perf_policy_clean: $(call descend,power/x86/$(@:_clean=),clean) tmon_clean: $(call descend,thermal/tmon,clean) freefall_clean: $(call descend,laptop/freefall,clean) build_clean: $(call descend,build,clean) clean: acpi_clean cgroup_clean cpupower_clean hv_clean firewire_clean lguest_clean \ perf_clean selftests_clean turbostat_clean spi_clean usb_clean virtio_clean \ vm_clean net_clean iio_clean x86_energy_perf_policy_clean tmon_clean \ freefall_clean build_clean libbpf_clean libsubcmd_clean liblockdep_clean \ gpio_clean objtool_clean leds_clean .PHONY: FORCE 1fc8d01bdb3821c1 /include/net/stp.h parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/net/stp.h')