/* cnode related routines for the coda kernel code (C) 1996 Peter Braam */ #include #include #include #include #include #include #include "coda_linux.h" static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2) { return memcmp(fid1, fid2, sizeof(*fid1)) == 0; } static const struct inode_operations coda_symlink_inode_operations = { .get_link = page_get_link, .setattr = coda_setattr, }; /* cnode.c */ static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr) { coda_vattr_to_iattr(inode, attr); if (S_ISREG(inode->i_mode)) { inode->i_op = &coda_file_inode_operations; inode->i_fop = &coda_file_operations; } else if (S_ISDIR(inode->i_mode)) { inode->i_op = &coda_dir_inode_operations; inode->i_fop = &coda_dir_operations; } else if (S_ISLNK(inode->i_mode)) { inode->i_op = &coda_symlink_inode_operations; inode_nohighmem(inode); inode->i_data.a_ops = &coda_symlink_aops; inode->i_mapping = &inode->i_data; } else init_special_inode(inode, inode->i_mode, huge_decode_dev(attr->va_rdev)); } static int coda_test_inode(struct inode *inode, void *data) { struct CodaFid *fid = (struct CodaFid *)data; struct coda_inode_info *cii = ITOC(inode); return coda_fideq(&cii->c_fid, fid); } static int coda_set_inode(struct inode *inode, void *data) { struct CodaFid *fid = (struct CodaFid *)data; struct coda_inode_info *cii = ITOC(inode); cii->c_fid = *fid; return 0; } struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid, struct coda_vattr * attr) { struct inode *inode; struct coda_inode_info *cii; unsigned long hash = coda_f2i(fid); inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid); if (!inode) return ERR_PTR(-ENOMEM); if (inode->i_state & I_NEW) { cii = ITOC(inode); /* we still need to set i_ino for things like stat(2) */ inode->i_ino = hash; /* inode is locked and unique, no need to grab cii->c_lock */ cii->c_mapcount = 0; unlock_new_inode(inode); } /* always replace the attributes, type might have changed */ coda_fill_inode(inode, attr); return inode; } /* this is effectively coda_iget: - get attributes (might be cached) - get the inode for the fid using vfs iget - link the two up if this is needed - fill in the attributes */ struct inode *coda_cnode_make(struct CodaFid *fid, struct super_block *sb) { struct coda_vattr attr; struct inode *inode; int error; /* We get inode numbers from Venus -- see venus source */ error = venus_getattr(sb, fid, &attr); if (error) return ERR_PTR(error); inode = coda_iget(sb, fid, &attr); if (IS_ERR(inode)) pr_warn("%s: coda_iget failed\n", __func__); return inode; } /* Although we treat Coda file identifiers as immutable, there is one * special case for files created during a disconnection where they may * not be globally unique. When an identifier collision is detected we * first try to flush the cached inode from the kernel and finally * resort to renaming/rehashing in-place. Userspace remembers both old * and new values of the identifier to handle any in-flight upcalls. * The real solution is to use globally unique UUIDs as identifiers, but * retrofitting the existing userspace code for this is non-trivial. */ void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid, struct CodaFid *newfid) { struct coda_inode_info *cii = ITOC(inode); unsigned long hash = coda_f2i(newfid); BUG_ON(!coda_fideq(&cii->c_fid, oldfid)); /* replace fid and rehash inode */ /* XXX we probably need to hold some lock here! */ remove_inode_hash(inode); cii->c_fid = *newfid; inode->i_ino = hash; __insert_inode_hash(inode, hash); } /* convert a fid to an inode. */ struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb) { struct inode *inode; unsigned long hash = coda_f2i(fid); if ( !sb ) { pr_warn("%s: no sb!\n", __func__); return NULL; } inode = ilookup5(sb, hash, coda_test_inode, fid); if ( !inode ) return NULL; /* we should never see newly created inodes because we intentionally * fail in the initialization callback */ BUG_ON(inode->i_state & I_NEW); return inode; } /* the CONTROL inode is made without asking attributes from Venus */ struct inode *coda_cnode_makectl(struct super_block *sb) { struct inode *inode = new_inode(sb); if (inode) { inode->i_ino = CTL_INO; inode->i_op = &coda_ioctl_inode_operations; inode->i_fop = &coda_ioctl_operations; inode->i_mode = 0444; return inode; } return ERR_PTR(-ENOMEM); } oundation.org>2017-01-29 13:50:06 -0800 committerLinus Torvalds <torvalds@linux-foundation.org>2017-01-29 13:50:06 -0800 commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch) tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /sound/soc/codecs/da7210.c 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 'sound/soc/codecs/da7210.c')