/* * (C) Copyright David Gibson , IBM Corporation. 2005. * * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 * USA */ #include "dtc.h" void data_free(struct data d) { struct marker *m, *nm; m = d.markers; while (m) { nm = m->next; free(m->ref); free(m); m = nm; } if (d.val) free(d.val); } struct data data_grow_for(struct data d, int xlen) { struct data nd; int newsize; if (xlen == 0) return d; nd = d; newsize = xlen; while ((d.len + xlen) > newsize) newsize *= 2; nd.val = xrealloc(d.val, newsize); return nd; } struct data data_copy_mem(const char *mem, int len) { struct data d; d = data_grow_for(empty_data, len); d.len = len; memcpy(d.val, mem, len); return d; } struct data data_copy_escape_string(const char *s, int len) { int i = 0; struct data d; char *q; d = data_grow_for(empty_data, len + 1); q = d.val; while (i < len) { char c = s[i++]; if (c == '\\') c = get_escape_char(s, &i); q[d.len++] = c; } q[d.len++] = '\0'; return d; } struct data data_copy_file(FILE *f, size_t maxlen) { struct data d = empty_data; while (!feof(f) && (d.len < maxlen)) { size_t chunksize, ret; if (maxlen == -1) chunksize = 4096; else chunksize = maxlen - d.len; d = data_grow_for(d, chunksize); ret = fread(d.val + d.len, 1, chunksize, f); if (ferror(f)) die("Error reading file into data: %s", strerror(errno)); if (d.len + ret < d.len) die("Overflow reading file into data\n"); d.len += ret; } return d; } struct data data_append_data(struct data d, const void *p, int len) { d = data_grow_for(d, len); memcpy(d.val + d.len, p, len); d.len += len; return d; } struct data data_insert_at_marker(struct data d, struct marker *m, const void *p, int len) { d = data_grow_for(d, len); memmove(d.val + m->offset + len, d.val + m->offset, d.len - m->offset); memcpy(d.val + m->offset, p, len); d.len += len; /* Adjust all markers after the one we're inserting at */ m = m->next; for_each_marker(m) m->offset += len; return d; } static struct data data_append_markers(struct data d, struct marker *m) { struct marker **mp = &d.markers; /* Find the end of the markerlist */ while (*mp) mp = &((*mp)->next); *mp = m; return d; } struct data data_merge(struct data d1, struct data d2) { struct data d; struct marker *m2 = d2.markers; d = data_append_markers(data_append_data(d1, d2.val, d2.len), m2); /* Adjust for the length of d1 */ for_each_marker(m2) m2->offset += d1.len; d2.markers = NULL; /* So data_free() doesn't clobber them */ data_free(d2); return d; } struct data data_append_integer(struct data d, uint64_t value, int bits) { uint8_t value_8; uint16_t value_16; uint32_t value_32; uint64_t value_64; switch (bits) { case 8: value_8 = value; return data_append_data(d, &value_8, 1); case 16: value_16 = cpu_to_fdt16(value); return data_append_data(d, &value_16, 2); case 32: value_32 = cpu_to_fdt32(value); return data_append_data(d, &value_32, 4); case 64: value_64 = cpu_to_fdt64(value); return data_append_data(d, &value_64, 8); default: die("Invalid literal size (%d)\n", bits); } } struct data data_append_re(struct data d, const struct fdt_reserve_entry *re) { struct fdt_reserve_entry bere; bere.address = cpu_to_fdt64(re->address); bere.size = cpu_to_fdt64(re->size); return data_append_data(d, &bere, sizeof(bere)); } struct data data_append_cell(struct data d, cell_t word) { return data_append_integer(d, word, sizeof(word) * 8); } struct data data_append_addr(struct data d, uint64_t addr) { return data_append_integer(d, addr, sizeof(addr) * 8); } struct data data_append_byte(struct data d, uint8_t byte) { return data_append_data(d, &byte, 1); } struct data data_append_zeroes(struct data d, int len) { d = data_grow_for(d, len); memset(d.val + d.len, 0, len); d.len += len; return d; } struct data data_append_align(struct data d, int align) { int newlen = ALIGN(d.len, align); return data_append_zeroes(d, newlen - d.len); } struct data data_add_marker(struct data d, enum markertype type, char *ref) { struct marker *m; m = xmalloc(sizeof(*m)); m->offset = d.len; m->type = type; m->ref = ref; m->next = NULL; return data_append_markers(d, m); } bool data_is_one_string(struct data d) { int i; int len = d.len; if (len == 0) return false; for (i = 0; i < len-1; i++) if (d.val[i] == '\0') return false; if (d.val[len-1] != '\0') return false; return true; } commit39cb2c9a316e77f6dfba96c543e55b6672d5a37e (patch) tree98fe974ee4e20121253de7f61fc8d01bdb3821c1 /tools/lib/api/fd 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 'tools/lib/api/fd')