--- /dev/null
+From c3456fb3e4712d0448592af3c5d644c9472cd3c1 Mon Sep 17 00:00:00 2001
+From: Daniel Vetter <daniel.vetter@ffwll.ch>
+Date: Mon, 10 Jun 2013 09:47:58 +0200
+Subject: drm/i915: prefer VBT modes for SVDO-LVDS over EDID
+
+From: Daniel Vetter <daniel.vetter@ffwll.ch>
+
+commit c3456fb3e4712d0448592af3c5d644c9472cd3c1 upstream.
+
+In
+
+commit 53d3b4d7778daf15900867336c85d3f8dd70600c
+Author: Egbert Eich <eich@suse.de>
+Date: Tue Jun 4 17:13:21 2013 +0200
+
+ drm/i915/sdvo: Use &intel_sdvo->ddc instead of intel_sdvo->i2c for DDC
+
+Egbert Eich fixed a long-standing bug where we simply used a
+non-working i2c controller to read the EDID for SDVO-LVDS panels.
+Unfortunately some machines seem to not be able to cope with the mode
+provided in the EDID. Specifically they seem to not be able to cope
+with a 4x pixel mutliplier instead of a 2x one, which seems to have
+been worked around by slightly changing the panels native mode in the
+VBT so that the dotclock is just barely above 50MHz.
+
+Since it took forever to notice the breakage it's fairly safe to
+assume that at least for SDVO-LVDS panels the VBT contains fairly sane
+data. So just switch around the order and use VBT modes first.
+
+v2: Also add EDID modes just in case, and spell Egbert correctly.
+
+v3: Elaborate a bit more about what's going on on Chris' machine.
+
+Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=65524
+Reported-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
+Cc: Egbert Eich <eich@suse.de>
+Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/gpu/drm/i915/intel_sdvo.c | 10 ++++++----
+ 1 file changed, 6 insertions(+), 4 deletions(-)
+
+--- a/drivers/gpu/drm/i915/intel_sdvo.c
++++ b/drivers/gpu/drm/i915/intel_sdvo.c
+@@ -1610,10 +1610,13 @@ static void intel_sdvo_get_lvds_modes(st
+ * arranged in priority order.
+ */
+ intel_ddc_get_modes(connector, &intel_sdvo->ddc);
+- if (list_empty(&connector->probed_modes) == false)
+- goto end;
+
+- /* Fetch modes from VBT */
++ /*
++ * Fetch modes from VBT. For SDVO prefer the VBT mode since some
++ * SDVO->LVDS transcoders can't cope with the EDID mode. Since
++ * drm_mode_probed_add adds the mode at the head of the list we add it
++ * last.
++ */
+ if (dev_priv->sdvo_lvds_vbt_mode != NULL) {
+ newmode = drm_mode_duplicate(connector->dev,
+ dev_priv->sdvo_lvds_vbt_mode);
+@@ -1625,7 +1628,6 @@ static void intel_sdvo_get_lvds_modes(st
+ }
+ }
+
+-end:
+ list_for_each_entry(newmode, &connector->probed_modes, head) {
+ if (newmode->type & DRM_MODE_TYPE_PREFERRED) {
+ intel_sdvo->sdvo_lvds_fixed_mode =
b43-stop-format-string-leaking-into-error-msgs.patch
ath9k-disable-powersave-by-default.patch
+drm-i915-prefer-vbt-modes-for-svdo-lvds-over-edid.patch
+swap-avoid-read_swap_cache_async-race-to-deadlock-while-waiting-on-discard-i-o-completion.patch
--- /dev/null
+From cbab0e4eec299e9059199ebe6daf48730be46d2b Mon Sep 17 00:00:00 2001
+From: Rafael Aquini <aquini@redhat.com>
+Date: Wed, 12 Jun 2013 14:04:49 -0700
+Subject: swap: avoid read_swap_cache_async() race to deadlock while waiting on discard I/O completion
+
+From: Rafael Aquini <aquini@redhat.com>
+
+commit cbab0e4eec299e9059199ebe6daf48730be46d2b upstream.
+
+read_swap_cache_async() can race against get_swap_page(), and stumble
+across a SWAP_HAS_CACHE entry in the swap map whose page wasn't brought
+into the swapcache yet.
+
+This transient swap_map state is expected to be transitory, but the
+actual placement of discard at scan_swap_map() inserts a wait for I/O
+completion thus making the thread at read_swap_cache_async() to loop
+around its -EEXIST case, while the other end at get_swap_page() is
+scheduled away at scan_swap_map(). This can leave the system deadlocked
+if the I/O completion happens to be waiting on the CPU waitqueue where
+read_swap_cache_async() is busy looping and !CONFIG_PREEMPT.
+
+This patch introduces a cond_resched() call to make the aforementioned
+read_swap_cache_async() busy loop condition to bail out when necessary,
+thus avoiding the subtle race window.
+
+Signed-off-by: Rafael Aquini <aquini@redhat.com>
+Acked-by: Johannes Weiner <hannes@cmpxchg.org>
+Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
+Acked-by: Hugh Dickins <hughd@google.com>
+Cc: Shaohua Li <shli@kernel.org>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ mm/swap_state.c | 18 +++++++++++++++++-
+ 1 file changed, 17 insertions(+), 1 deletion(-)
+
+--- a/mm/swap_state.c
++++ b/mm/swap_state.c
+@@ -315,8 +315,24 @@ struct page *read_swap_cache_async(swp_e
+ * Swap entry may have been freed since our caller observed it.
+ */
+ err = swapcache_prepare(entry);
+- if (err == -EEXIST) { /* seems racy */
++ if (err == -EEXIST) {
+ radix_tree_preload_end();
++ /*
++ * We might race against get_swap_page() and stumble
++ * across a SWAP_HAS_CACHE swap_map entry whose page
++ * has not been brought into the swapcache yet, while
++ * the other end is scheduled away waiting on discard
++ * I/O completion at scan_swap_map().
++ *
++ * In order to avoid turning this transitory state
++ * into a permanent loop around this -EEXIST case
++ * if !CONFIG_PREEMPT and the I/O completion happens
++ * to be waiting on the CPU waitqueue where we are now
++ * busy looping, we just conditionally invoke the
++ * scheduler here, if there are some more important
++ * tasks to run.
++ */
++ cond_resched();
+ continue;
+ }
+ if (err) { /* swp entry is obsolete ? */
projects / thirdparty / kernel / stable-queue.git / commitdiff
