/* * JFFS2 -- Journalling Flash File System, Version 2. * * Copyright © 2001-2007 Red Hat, Inc. * Copyright © 2004-2010 David Woodhouse * * Created by David Woodhouse * * For licensing information, see the file 'LICENCE' in this directory. * */ #if !defined(__KERNEL__) && !defined(__ECOS) #error "The userspace support got too messy and was removed. Update your mkfs.jffs2" #endif #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include "nodelist.h" #include "compr.h" /* Plan: call deflate() with avail_in == *sourcelen, avail_out = *dstlen - 12 and flush == Z_FINISH. If it doesn't manage to finish, call it again with avail_in == 0 and avail_out set to the remaining 12 bytes for it to clean up. Q: Is 12 bytes sufficient? */ #define STREAM_END_SPACE 12 static DEFINE_MUTEX(deflate_mutex); static DEFINE_MUTEX(inflate_mutex); static z_stream inf_strm, def_strm; #ifdef __KERNEL__ /* Linux-only */ #include #include #include static int __init alloc_workspaces(void) { def_strm.workspace = vmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL)); if (!def_strm.workspace) return -ENOMEM; jffs2_dbg(1, "Allocated %d bytes for deflate workspace\n", zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL)); inf_strm.workspace = vmalloc(zlib_inflate_workspacesize()); if (!inf_strm.workspace) { vfree(def_strm.workspace); return -ENOMEM; } jffs2_dbg(1, "Allocated %d bytes for inflate workspace\n", zlib_inflate_workspacesize()); return 0; } static void free_workspaces(void) { vfree(def_strm.workspace); vfree(inf_strm.workspace); } #else #define alloc_workspaces() (0) #define free_workspaces() do { } while(0) #endif /* __KERNEL__ */ static int jffs2_zlib_compress(unsigned char *data_in, unsigned char *cpage_out, uint32_t *sourcelen, uint32_t *dstlen) { int ret; if (*dstlen <= STREAM_END_SPACE) return -1; mutex_lock(&deflate_mutex); if (Z_OK != zlib_deflateInit(&def_strm, 3)) { pr_warn("deflateInit failed\n"); mutex_unlock(&deflate_mutex); return -1; } def_strm.next_in = data_in; def_strm.total_in = 0; def_strm.next_out = cpage_out; def_strm.total_out = 0; while (def_strm.total_out < *dstlen - STREAM_END_SPACE && def_strm.total_in < *sourcelen) { def_strm.avail_out = *dstlen - (def_strm.total_out + STREAM_END_SPACE); def_strm.avail_in = min_t(unsigned long, (*sourcelen-def_strm.total_in), def_strm.avail_out); jffs2_dbg(1, "calling deflate with avail_in %ld, avail_out %ld\n", def_strm.avail_in, def_strm.avail_out); ret = zlib_deflate(&def_strm, Z_PARTIAL_FLUSH); jffs2_dbg(1, "deflate returned with avail_in %ld, avail_out %ld, total_in %ld, total_out %ld\n", def_strm.avail_in, def_strm.avail_out, def_strm.total_in, def_strm.total_out); if (ret != Z_OK) { jffs2_dbg(1, "deflate in loop returned %d\n", ret); zlib_deflateEnd(&def_strm); mutex_unlock(&deflate_mutex); return -1; } } def_strm.avail_out += STREAM_END_SPACE; def_strm.avail_in = 0; ret = zlib_deflate(&def_strm, Z_FINISH); zlib_deflateEnd(&def_strm); if (ret != Z_STREAM_END) { jffs2_dbg(1, "final deflate returned %d\n", ret); ret = -1; goto out; } if (def_strm.total_out >= def_strm.total_in) { jffs2_dbg(1, "zlib compressed %ld bytes into %ld; failing\n", def_strm.total_in, def_strm.total_out); ret = -1; goto out; } jffs2_dbg(1, "zlib compressed %ld bytes into %ld\n", def_strm.total_in, def_strm.total_out); *dstlen = def_strm.total_out; *sourcelen = def_strm.total_in; ret = 0; out: mutex_unlock(&deflate_mutex); return ret; } static int jffs2_zlib_decompress(unsigned char *data_in, unsigned char *cpage_out, uint32_t srclen, uint32_t destlen) { int ret; int wbits = MAX_WBITS; mutex_lock(&inflate_mutex); inf_strm.next_in = data_in; inf_strm.avail_in = srclen; inf_strm.total_in = 0; inf_strm.next_out = cpage_out; inf_strm.avail_out = destlen; inf_strm.total_out = 0; /* If it's deflate, and it's got no preset dictionary, then we can tell zlib to skip the adler32 check. */ if (srclen > 2 && !(data_in[1] & PRESET_DICT) && ((data_in[0] & 0x0f) == Z_DEFLATED) && !(((data_in[0]<<8) + data_in[1]) % 31)) { jffs2_dbg(2, "inflate skipping adler32\n"); wbits = -((data_in[0] >> 4) + 8); inf_strm.next_in += 2; inf_strm.avail_in -= 2; } else { /* Let this remain D1 for now -- it should never happen */ jffs2_dbg(1, "inflate not skipping adler32\n"); } if (Z_OK != zlib_inflateInit2(&inf_strm, wbits)) { pr_warn("inflateInit failed\n"); mutex_unlock(&inflate_mutex); return 1; } while((ret = zlib_inflate(&inf_strm, Z_FINISH)) == Z_OK) ; if (ret != Z_STREAM_END) { pr_notice("inflate returned %d\n", ret); } zlib_inflateEnd(&inf_strm); mutex_unlock(&inflate_mutex); return 0; } static struct jffs2_compressor jffs2_zlib_comp = { .priority = JFFS2_ZLIB_PRIORITY, .name = "zlib", .compr = JFFS2_COMPR_ZLIB, .compress = &jffs2_zlib_compress, .decompress = &jffs2_zlib_decompress, #ifdef JFFS2_ZLIB_DISABLED .disabled = 1, #else .disabled = 0, #endif }; int __init jffs2_zlib_init(void) { int ret; ret = alloc_workspaces(); if (ret) return ret; ret = jffs2_register_compressor(&jffs2_zlib_comp); if (ret) free_workspaces(); return ret; } void jffs2_zlib_exit(void) { jffs2_unregister_compressor(&jffs2_zlib_comp); free_workspaces(); } 9d4c6529a5f7b9206e405 (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/trace/perf.h')