#ifndef _BTRFS_SYSFS_H_
#define _BTRFS_SYSFS_H_
/*
* Data exported through sysfs
*/
extern u64 btrfs_debugfs_test;
enum btrfs_feature_set {
FEAT_COMPAT,
FEAT_COMPAT_RO,
FEAT_INCOMPAT,
FEAT_MAX
};
#define __INIT_KOBJ_ATTR(_name, _mode, _show, _store) \
{ \
.attr = { .name = __stringify(_name), .mode = _mode }, \
.show = _show, \
.store = _store, \
}
#define BTRFS_ATTR_RW(_name, _show, _store) \
static struct kobj_attribute btrfs_attr_##_name = \
__INIT_KOBJ_ATTR(_name, 0644, _show, _store)
#define BTRFS_ATTR(_name, _show) \
static struct kobj_attribute btrfs_attr_##_name = \
__INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
#define BTRFS_ATTR_PTR(_name) (&btrfs_attr_##_name.attr)
#define BTRFS_RAID_ATTR(_name, _show) \
static struct kobj_attribute btrfs_raid_attr_##_name = \
__INIT_KOBJ_ATTR(_name, 0444, _show, NULL)
#define BTRFS_RAID_ATTR_PTR(_name) (&btrfs_raid_attr_##_name.attr)
struct btrfs_feature_attr {
struct kobj_attribute kobj_attr;
enum btrfs_feature_set feature_set;
u64 feature_bit;
};
#define BTRFS_FEAT_ATTR(_name, _feature_set, _prefix, _feature_bit) \
static struct btrfs_feature_attr btrfs_attr_##_name = { \
.kobj_attr = __INIT_KOBJ_ATTR(_name, S_IRUGO, \
btrfs_feature_attr_show, \
btrfs_feature_attr_store), \
.feature_set = _feature_set, \
.feature_bit = _prefix ##_## _feature_bit, \
}
#define BTRFS_FEAT_ATTR_PTR(_name) (&btrfs_attr_##_name.kobj_attr.attr)
#define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
#define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
#define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
/* convert from attribute */
static inline struct btrfs_feature_attr *
to_btrfs_feature_attr(struct kobj_attribute *a)
{
return container_of(a, struct btrfs_feature_attr, kobj_attr);
}
static inline struct kobj_attribute *attr_to_btrfs_attr(struct attribute *attr)
{
return container_of(attr, struct kobj_attribute, attr);
}
static inline struct btrfs_feature_attr *
attr_to_btrfs_feature_attr(struct attribute *attr)
{
return to_btrfs_feature_attr(attr_to_btrfs_attr(attr));
}
char *btrfs_printable_features(enum btrfs_feature_set set, u64 flags);
extern const char * const btrfs_feature_set_names[3];
extern struct kobj_type space_info_ktype;
extern struct kobj_type btrfs_raid_ktype;
int btrfs_sysfs_add_device_link(struct btrfs_fs_devices *fs_devices,
struct btrfs_device *one_device);
int btrfs_sysfs_rm_device_link(struct btrfs_fs_devices *fs_devices,
struct btrfs_device *one_device);
int btrfs_sysfs_add_fsid(struct btrfs_fs_devices *fs_devs,
struct kobject *parent);
int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs);
void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs);
void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
u64 bit, enum btrfs_feature_set set);
#endif /* _BTRFS_SYSFS_H_ */
rivate-remove&id=39cb2c9a316e77f6dfba96c543e55b6672d5a37e'>tools/perf/tests/code-reading.c
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>