Partially revert commit 5f501d555653 ("binfmt_elf: reintroduce using
MAP_FIXED_NOREPLACE").
At least ia64 has ET_EXEC PT_LOAD segments that are not virtual-address
contiguous (but _are_ file-offset contiguous). This would result in
giant mapping attempts to cover the entire span, including the virtual
address range hole. Disable total_mapping_size for ET_EXEC, which
reduces the MAP_FIXED_NOREPLACE coverage to only the first PT_LOAD:
$ readelf -lW /usr/bin/gcc
...
Program Headers:
Type Offset VirtAddr PhysAddr FileSiz MemSiz ...
...
LOAD 0x000000 0x4000000000000000 0x4000000000000000 0x00b5a0 0x00b5a0 ...
LOAD 0x00b5a0 0x600000000000b5a0 0x600000000000b5a0 0x0005ac 0x000710 ...
...
^^^^^^^^ ^^^^^^^^^^^^^^^^^^ ^^^^^^^^ ^^^^^^^^
File offset range : 0x000000-0x00bb4c
0x00bb4c bytes
Virtual address range : 0x4000000000000000-0x600000000000bcb0
0x200000000000bcb0 bytes
Ironically, this is the reverse of the problem that originally caused
problems with ET_EXEC and MAP_FIXED_NOREPLACE: overlaps. This problem is
with holes. Future work could restore full coverage if load_elf_binary()
were to perform mappings in a separate phase from the loading (where
it could resolve both overlaps and holes).
Cc: Alexander Viro <viro(a)zeniv.linux.org.uk>
Cc: Eric Biederman <ebiederm(a)xmission.com>
Cc: linux-fsdevel(a)vger.kernel.org
Cc: linux-mm(a)kvack.org
Reported-by: matoro <matoro_mailinglist_kernel(a)matoro.tk>
Reported-by: John Paul Adrian Glaubitz <glaubitz(a)physik.fu-berlin.de>
Fixes: 5f501d555653 ("binfmt_elf: reintroduce using MAP_FIXED_NOREPLACE")
Link: https://lore.kernel.org/r/a3edd529-c42d-3b09-135c-7e98a15b150f@leemhuis.info
Cc: stable(a)vger.kernel.org
Signed-off-by: Kees Cook <keescook(a)chromium.org>
---
matoro (or anyone else) can you please test this?
---
fs/binfmt_elf.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 9bea703ed1c2..474b44032c65 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -1136,14 +1136,25 @@ static int load_elf_binary(struct linux_binprm *bprm)
* is then page aligned.
*/
load_bias = ELF_PAGESTART(load_bias - vaddr);
- }
- /*
- * Calculate the entire size of the ELF mapping (total_size).
- * (Note that first_pt_load is set to false later once the
- * initial mapping is performed.)
- */
- if (first_pt_load) {
+ /*
+ * Calculate the entire size of the ELF mapping
+ * (total_size), used for the initial mapping,
+ * due to first_pt_load which is set to false later
+ * once the initial mapping is performed.
+ *
+ * Note that this is only sensible when the LOAD
+ * segments are contiguous (or overlapping). If
+ * used for LOADs that are far apart, this would
+ * cause the holes between LOADs to be mapped,
+ * running the risk of having the mapping fail,
+ * as it would be larger than the ELF file itself.
+ *
+ * As a result, only ET_DYN does this, since
+ * some ET_EXEC (e.g. ia64) may have virtual
+ * memory holes between LOADs.
+ *
+ */
total_size = total_mapping_size(elf_phdata,
elf_ex->e_phnum);
if (!total_size) {
--
2.32.0
Most eDP panel functions only work correctly when the panel is not in
self-refresh. In particular, analogix_dp_bridge_disable() tends to hit
AUX channel errors if the panel is in self-refresh.
Given the above, it appears that so far, this driver assumes that we are
never in self-refresh when it comes time to fully disable the bridge.
Prior to commit 846c7dfc1193 ("drm/atomic: Try to preserve the crtc
enabled state in drm_atomic_remove_fb, v2."), this tended to be true,
because we would automatically disable the pipe when framebuffers were
removed, and so we'd typically disable the bridge shortly after the last
display activity.
However, that is not guaranteed: an idle (self-refresh) display pipe may
be disabled, e.g., when switching CRTCs. We need to exit PSR first.
Stable notes: this is definitely a bugfix, and the bug has likely
existed in some form for quite a while. It may predate the "PSR helpers"
refactor, but the code looked very different before that, and it's
probably not worth rewriting the fix.
Cc: <stable(a)vger.kernel.org>
Fixes: 6c836d965bad ("drm/rockchip: Use the helpers for PSR")
Signed-off-by: Brian Norris <briannorris(a)chromium.org>
---
(no changes since v1)
.../drm/bridge/analogix/analogix_dp_core.c | 42 +++++++++++++++++--
1 file changed, 38 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index b7d2e4449cfa..6ee0f62a7161 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1268,6 +1268,25 @@ static int analogix_dp_bridge_attach(struct drm_bridge *bridge,
return 0;
}
+static
+struct drm_crtc *analogix_dp_get_old_crtc(struct analogix_dp_device *dp,
+ struct drm_atomic_state *state)
+{
+ struct drm_encoder *encoder = dp->encoder;
+ struct drm_connector *connector;
+ struct drm_connector_state *conn_state;
+
+ connector = drm_atomic_get_old_connector_for_encoder(state, encoder);
+ if (!connector)
+ return NULL;
+
+ conn_state = drm_atomic_get_old_connector_state(state, connector);
+ if (!conn_state)
+ return NULL;
+
+ return conn_state->crtc;
+}
+
static
struct drm_crtc *analogix_dp_get_new_crtc(struct analogix_dp_device *dp,
struct drm_atomic_state *state)
@@ -1448,14 +1467,16 @@ analogix_dp_bridge_atomic_disable(struct drm_bridge *bridge,
{
struct drm_atomic_state *old_state = old_bridge_state->base.state;
struct analogix_dp_device *dp = bridge->driver_private;
- struct drm_crtc *crtc;
+ struct drm_crtc *old_crtc, *new_crtc;
+ struct drm_crtc_state *old_crtc_state = NULL;
struct drm_crtc_state *new_crtc_state = NULL;
+ int ret;
- crtc = analogix_dp_get_new_crtc(dp, old_state);
- if (!crtc)
+ new_crtc = analogix_dp_get_new_crtc(dp, old_state);
+ if (!new_crtc)
goto out;
- new_crtc_state = drm_atomic_get_new_crtc_state(old_state, crtc);
+ new_crtc_state = drm_atomic_get_new_crtc_state(old_state, new_crtc);
if (!new_crtc_state)
goto out;
@@ -1464,6 +1485,19 @@ analogix_dp_bridge_atomic_disable(struct drm_bridge *bridge,
return;
out:
+ old_crtc = analogix_dp_get_old_crtc(dp, old_state);
+ if (old_crtc) {
+ old_crtc_state = drm_atomic_get_old_crtc_state(old_state,
+ old_crtc);
+
+ /* When moving from PSR to fully disabled, exit PSR first. */
+ if (old_crtc_state && old_crtc_state->self_refresh_active) {
+ ret = analogix_dp_disable_psr(dp);
+ if (ret)
+ DRM_ERROR("Failed to disable psr (%d)\n", ret);
+ }
+ }
+
analogix_dp_bridge_disable(bridge);
}
--
2.35.1.574.g5d30c73bfb-goog
It's possible to change which CRTC is in use for a given
connector/encoder/bridge while we're in self-refresh without fully
disabling the connector/encoder/bridge along the way. This can confuse
the bridge encoder/bridge, because
(a) it needs to track the SR state (trying to perform "active"
operations while the panel is still in SR can be Bad(TM)); and
(b) it tracks the SR state via the CRTC state (and after the switch, the
previous SR state is lost).
Thus, we need to either somehow carry the self-refresh state over to the
new CRTC, or else force an encoder/bridge self-refresh transition during
such a switch.
I choose the latter, so we disable the encoder (and exit PSR) before
attaching it to the new CRTC (where we can continue to assume a clean
(non-self-refresh) state).
This fixes PSR issues seen on Rockchip RK3399 systems with
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c.
Cc: <stable(a)vger.kernel.org>
Fixes: 1452c25b0e60 ("drm: Add helpers to kick off self refresh mode in drivers")
Signed-off-by: Brian Norris <briannorris(a)chromium.org>
---
drivers/gpu/drm/drm_atomic_helper.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 9603193d2fa1..74161d007894 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1011,9 +1011,19 @@ crtc_needs_disable(struct drm_crtc_state *old_state,
return drm_atomic_crtc_effectively_active(old_state);
/*
- * We need to run through the crtc_funcs->disable() function if the CRTC
- * is currently on, if it's transitioning to self refresh mode, or if
- * it's in self refresh mode and needs to be fully disabled.
+ * We need to disable bridge(s) and CRTC if we're transitioning out of
+ * self-refresh and changing CRTCs at the same time, because the
+ * bridge tracks self-refresh status via CRTC state.
+ */
+ if (old_state->self_refresh_active && new_state->enable &&
+ old_state->crtc != new_state->crtc)
+ return true;
+
+ /*
+ * We also need to run through the crtc_funcs->disable() function if
+ * the CRTC is currently on, if it's transitioning to self refresh
+ * mode, or if it's in self refresh mode and needs to be fully
+ * disabled.
*/
return old_state->active ||
(old_state->self_refresh_active && !new_state->active) ||
--
2.35.1.265.g69c8d7142f-goog