From: Bart Van Assche <bart.vanassche(a)wdc.com>
Since SCSI scanning occurs asynchronously, since sd_revalidate_disk()
is called from sd_probe_async() and since sd_revalidate_disk() calls
sd_zbc_read_zones() it can happen that sd_zbc_read_zones() is called
concurrently with operations referencing a drive zone bitmaps and number
of zones. Make sure that this race does not cause failures when
revalidate does not detect any change by making the following changes to
sd_zbc_setup():
- Ensure that sd_zbc_setup_seq_zones_bitmap() does not change any
ZBC metadata in the request queue.
- Only modify the ZBC information in the request queue that has
changed. If the number of zones has changed, update q->nr_zones,
q->seq_zones_wlock and q->seq_zones_bitmap. If the type of some
zones has changed but not the number of zones, only update the
zone type information.
Signed-off-by: Bart Van Assche <bart.vanassche(a)wdc.com>
[Damien] Updated commit message and changed nr_zones/bitmap swap order.
Signed-off-by: Damien Le Moal <damien.lemoal(a)wdc.com>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: stable(a)vger.kernel.org
---
drivers/scsi/sd_zbc.c | 45 +++++++++++++++++++++++++++------------------
1 file changed, 27 insertions(+), 18 deletions(-)
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index b59454ed5087..39ddbe92769c 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -551,14 +551,13 @@ static sector_t sd_zbc_get_seq_zones(struct scsi_disk *sdkp, unsigned char *buf,
}
/**
- * sd_zbc_setup_seq_zones_bitmap - Initialize the disk seq zone bitmap.
+ * sd_zbc_setup_seq_zones_bitmap - Initialize a seq zone bitmap.
* @sdkp: target disk
*
* Allocate a zone bitmap and initialize it by identifying sequential zones.
*/
-static int sd_zbc_setup_seq_zones_bitmap(struct scsi_disk *sdkp)
+static unsigned long *sd_zbc_setup_seq_zones_bitmap(struct scsi_disk *sdkp)
{
- struct request_queue *q = sdkp->disk->queue;
unsigned long *seq_zones_bitmap;
sector_t lba = 0;
unsigned char *buf;
@@ -566,7 +565,7 @@ static int sd_zbc_setup_seq_zones_bitmap(struct scsi_disk *sdkp)
seq_zones_bitmap = sd_zbc_alloc_zone_bitmap(sdkp);
if (!seq_zones_bitmap)
- return -ENOMEM;
+ return ERR_PTR(-ENOMEM);
buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL);
if (!buf)
@@ -589,12 +588,9 @@ static int sd_zbc_setup_seq_zones_bitmap(struct scsi_disk *sdkp)
kfree(buf);
if (ret) {
kfree(seq_zones_bitmap);
- return ret;
+ return ERR_PTR(ret);
}
-
- q->seq_zones_bitmap = seq_zones_bitmap;
-
- return 0;
+ return seq_zones_bitmap;
}
static void sd_zbc_cleanup(struct scsi_disk *sdkp)
@@ -630,24 +626,37 @@ static int sd_zbc_setup(struct scsi_disk *sdkp)
* of zones changed.
*/
if (sdkp->nr_zones != q->nr_zones) {
+ struct request_queue *q = sdkp->disk->queue;
+ unsigned long *seq_zones_wlock = NULL, *seq_zones_bitmap = NULL;
+ size_t zone_bitmap_size;
- sd_zbc_cleanup(sdkp);
-
- q->nr_zones = sdkp->nr_zones;
if (sdkp->nr_zones) {
- q->seq_zones_wlock = sd_zbc_alloc_zone_bitmap(sdkp);
- if (!q->seq_zones_wlock) {
+ seq_zones_wlock = sd_zbc_alloc_zone_bitmap(sdkp);
+ if (!seq_zones_wlock) {
ret = -ENOMEM;
goto err;
}
- ret = sd_zbc_setup_seq_zones_bitmap(sdkp);
- if (ret) {
- sd_zbc_cleanup(sdkp);
+ seq_zones_bitmap = sd_zbc_setup_seq_zones_bitmap(sdkp);
+ if (IS_ERR(seq_zones_bitmap)) {
+ ret = PTR_ERR(seq_zones_bitmap);
+ kfree(seq_zones_wlock);
goto err;
}
}
-
+ zone_bitmap_size = BITS_TO_LONGS(sdkp->nr_zones) *
+ sizeof(unsigned long);
+ if (q->nr_zones != sdkp->nr_zones) {
+ swap(q->seq_zones_wlock, seq_zones_wlock);
+ swap(q->seq_zones_bitmap, seq_zones_bitmap);
+ q->nr_zones = sdkp->nr_zones;
+ } else if (memcmp(q->seq_zones_bitmap, seq_zones_bitmap,
+ zone_bitmap_size) != 0) {
+ memcpy(q->seq_zones_bitmap, seq_zones_bitmap,
+ zone_bitmap_size);
+ }
+ kfree(seq_zones_wlock);
+ kfree(seq_zones_bitmap);
}
return 0;
--
2.14.3
When sd_revalidate() is executed for a ZBC disk (zoned block device),
sd_zbc_read_zones() is called to revalidate the disk zone configuration.
This executes sd_zbc_check_zone_size() to check that the disk zone sizes
are in line with the defined constraints (all zones must be the same
size and a power of 2 number of LBAs). As part of its execution,
sd_zbc_check_zone_size() was temporarily setting sdkp->zone_blocks to 0.
If during the execution of sd_zbc_check_zone_size() within
sd_revalidate() context, another context issues a command which
references sdkp->zone_blocks to check zone alignment of the command
(e.g. a zone reset is issued and sd_zbc_setup_reset_cmnd() is called),
an invalid value for the disk zone size is used and the alignment check
fails.
Simply fix this by using an on-stack variable inside
sd_zbc_check_zone_size() instead of directly using sdkp->zone_blocks.
This change is valid for both revalidate as well as for the first scan
of the device.
Signed-off-by: Damien Le Moal <damien.lemoal(a)wdc.com>
Cc: <stable(a)vger.kernel.org>
---
drivers/scsi/sd_zbc.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
index 89cf4498f535..b59454ed5087 100644
--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -403,6 +403,7 @@ static int sd_zbc_check_capacity(struct scsi_disk *sdkp, unsigned char *buf)
*/
static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
{
+ u64 sdkp_zone_blocks = sdkp->zone_blocks;
u64 zone_blocks = 0;
sector_t block = 0;
unsigned char *buf;
@@ -412,8 +413,6 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
int ret;
u8 same;
- sdkp->zone_blocks = 0;
-
/* Get a buffer */
buf = kmalloc(SD_ZBC_BUF_SIZE, GFP_KERNEL);
if (!buf)
@@ -446,11 +445,11 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
/* Parse zone descriptors */
while (rec < buf + buf_len) {
zone_blocks = get_unaligned_be64(&rec[8]);
- if (sdkp->zone_blocks == 0) {
- sdkp->zone_blocks = zone_blocks;
- } else if (zone_blocks != sdkp->zone_blocks &&
+ if (sdkp_zone_blocks == 0) {
+ sdkp_zone_blocks = zone_blocks;
+ } else if (zone_blocks != sdkp_zone_blocks &&
(block + zone_blocks < sdkp->capacity
- || zone_blocks > sdkp->zone_blocks)) {
+ || zone_blocks > sdkp_zone_blocks)) {
zone_blocks = 0;
goto out;
}
@@ -467,7 +466,7 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
} while (block < sdkp->capacity);
- zone_blocks = sdkp->zone_blocks;
+ zone_blocks = sdkp_zone_blocks;
out:
if (!zone_blocks) {
--
2.14.3
As it turns out, the aux block being off was not the real problem here,
as transition from D3 to D0 is mandated by the DP spec to take a maximum
of 1ms, whereas we're allowed a 100ms timeframe to respond to ESI irqs.
The real problem here is a bit more subtle.
When doing a modeset where the problem of the sink timing out to our
sideband requests when transitioning from D3 to D0 occurs, the timeout
is from the aux block not coming on. However, nothing else times out
other than the initial phy_up message because the DPCD on call in
intel_ddi_enable_dp() ends up waking up the AUX block on the hub, not
the phy_up sideband message. This means that the real fix we need is to
use the DPMS on before sending a phy_up to ensure that the hub is ready
to accept sideband messages.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan(a)intel.com>
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Cc: Laura Abbott <labbott(a)redhat.com>
Cc: stable(a)vger.kernel.org
Fixes: ad260ab32a4d9 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.")
---
Sorry for all the spam guys! This is my last attempt at getting this
patch to actually come up on intel-gfx's patchwork page instead of
dri-devel. I have no idea what is going on with patchwork right now :|,
but maybe removing dri-devel from the CC entirely will help.
drivers/gpu/drm/i915/intel_ddi.c | 6 +++++-
drivers/gpu/drm/i915/intel_dp_mst.c | 1 +
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index a6672a9abd85..9bd675f73f7b 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -2324,7 +2324,11 @@ static void intel_ddi_pre_enable_dp(struct intel_encoder *encoder,
intel_prepare_dp_ddi_buffers(encoder, crtc_state);
intel_ddi_init_dp_buf_reg(encoder);
- intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+ /* for MST, we do DPMS_ON outside of here so that DPMS_ON can happen
+ * before drm_dp_send_power_updown_phy()
+ */
+ if (!intel_dp->is_mst)
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
intel_dp_start_link_train(intel_dp);
if (port != PORT_A || INTEL_GEN(dev_priv) >= 9)
intel_dp_stop_link_train(intel_dp);
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index c3de0918ee13..eff9a4eae1f0 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -223,6 +223,7 @@ static void intel_mst_pre_enable_dp(struct intel_encoder *encoder,
DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, true);
if (intel_dp->active_mst_links == 0)
intel_dig_port->base.pre_enable(&intel_dig_port->base,
--
2.14.3
As it turns out, the aux block being off was not the real problem here,
as transition from D3 to D0 is mandated by the DP spec to take a maximum
of 1ms, whereas we're allowed a 100ms timeframe to respond to ESI irqs.
The real problem here is a bit more subtle.
When doing a modeset where the problem of the sink timing out to our
sideband requests when transitioning from D3 to D0 occurs, the timeout
is from the aux block not coming on. However, nothing else times out
other than the initial phy_up message because the DPCD on call in
intel_ddi_enable_dp() ends up waking up the AUX block on the hub, not
the phy_up sideband message. This means that the real fix we need is to
use the DPMS on before sending a phy_up to ensure that the hub is ready
to accept sideband messages.
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan(a)intel.com>
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Cc: Laura Abbott <labbott(a)redhat.com>
Cc: stable(a)vger.kernel.org
Fixes: ad260ab32a4d9 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.")
---
drivers/gpu/drm/i915/intel_ddi.c | 6 +++++-
drivers/gpu/drm/i915/intel_dp_mst.c | 1 +
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index a6672a9abd85..9bd675f73f7b 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -2324,7 +2324,11 @@ static void intel_ddi_pre_enable_dp(struct intel_encoder *encoder,
intel_prepare_dp_ddi_buffers(encoder, crtc_state);
intel_ddi_init_dp_buf_reg(encoder);
- intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
+ /* for MST, we do DPMS_ON outside of here so that DPMS_ON can happen
+ * before drm_dp_send_power_updown_phy()
+ */
+ if (!intel_dp->is_mst)
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
intel_dp_start_link_train(intel_dp);
if (port != PORT_A || INTEL_GEN(dev_priv) >= 9)
intel_dp_stop_link_train(intel_dp);
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index c3de0918ee13..eff9a4eae1f0 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -223,6 +223,7 @@ static void intel_mst_pre_enable_dp(struct intel_encoder *encoder,
DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
+ intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, true);
if (intel_dp->active_mst_links == 0)
intel_dig_port->base.pre_enable(&intel_dig_port->base,
--
2.14.3
The patch titled
Subject: mm/memblock: fix potential issue in memblock_search_pfn_nid()
has been removed from the -mm tree. Its filename was
mm-memblock-fix-potential-issue-in-memblock_search_pfn_nid.patch
This patch was dropped because it was nacked
------------------------------------------------------
From: Wei Yang <richard.weiyang(a)gmail.com>
Subject: mm/memblock: fix potential issue in memblock_search_pfn_nid()
memblock_search_pfn_nid() returns the nid and the [start|end]_pfn of the
memory region where pfn sits in. While the calculation of start_pfn has
potential issue when the regions base is not page aligned.
For example, we assume PAGE_SHIFT is 12 and base is 0x1234. Current
implementation would return 1 while this is not correct.
This patch fixes this by using PFN_UP().
The original commit is commit e76b63f80d93 ("memblock, numa: binary search
node id") and merged in v3.12.
Link: http://lkml.kernel.org/r/20180330033055.22340-1-richard.weiyang@gmail.com
Fixes: e76b63f80d93 ("memblock, numa: binary search node id")
Signed-off-by: Wei Yang <richard.weiyang(a)gmail.com>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Yinghai Lu <yinghai(a)kernel.org>
Cc: Jia He <hejianet(a)gmail.com>
Cc: <stable(a)vger.kernel.org> [3.12+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/memblock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN mm/memblock.c~mm-memblock-fix-potential-issue-in-memblock_search_pfn_nid mm/memblock.c
--- a/mm/memblock.c~mm-memblock-fix-potential-issue-in-memblock_search_pfn_nid
+++ a/mm/memblock.c
@@ -1646,7 +1646,7 @@ int __init_memblock memblock_search_pfn_
if (mid == -1)
return -1;
- *start_pfn = PFN_DOWN(type->regions[mid].base);
+ *start_pfn = PFN_UP(type->regions[mid].base);
*end_pfn = PFN_DOWN(type->regions[mid].base + type->regions[mid].size);
return type->regions[mid].nid;
_
Patches currently in -mm which might be from richard.weiyang(a)gmail.com are
mm-check-__highest_present_sectioin_nr-directly-in-memory_dev_init.patch
The patch titled
Subject: lib: fix stall in __bitmap_parselist()
has been added to the -mm tree. Its filename is
lib-fix-stall-in-__bitmap_parselist.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/lib-fix-stall-in-__bitmap_parselis…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/lib-fix-stall-in-__bitmap_parselis…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Yury Norov <ynorov(a)caviumnetworks.com>
Subject: lib: fix stall in __bitmap_parselist()
syzbot is catching stalls at __bitmap_parselist()
(https://syzkaller.appspot.com/bug?id=ad7e0351fbc90535558514a71cd3edc1168199…).
The trigger is
unsigned long v = 0;
bitmap_parselist("7:,", &v, BITS_PER_LONG);
which results in hitting infinite loop at
while (a <= b) {
off = min(b - a + 1, used_size);
bitmap_set(maskp, a, off);
a += group_size;
}
due to used_size == group_size == 0.
Link: http://lkml.kernel.org/r/20180404162647.15763-1-ynorov@caviumnetworks.com
Fixes: 0a5ce0831d04382a ("lib/bitmap.c: make bitmap_parselist() thread-safe and much faster")
Signed-off-by: Yury Norov <ynorov(a)caviumnetworks.com>
Reported-by: Tetsuo Handa <penguin-kernel(a)I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+6887cbb011c8054e8a3d(a)syzkaller.appspotmail.com>
Cc: Noam Camus <noamca(a)mellanox.com>
Cc: Rasmus Villemoes <linux(a)rasmusvillemoes.dk>
Cc: Matthew Wilcox <mawilcox(a)microsoft.com>
Cc: Mauro Carvalho Chehab <mchehab(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
lib/bitmap.c | 2 +-
lib/test_bitmap.c | 4 ++++
2 files changed, 5 insertions(+), 1 deletion(-)
diff -puN lib/bitmap.c~lib-fix-stall-in-__bitmap_parselist lib/bitmap.c
--- a/lib/bitmap.c~lib-fix-stall-in-__bitmap_parselist
+++ a/lib/bitmap.c
@@ -607,7 +607,7 @@ static int __bitmap_parselist(const char
/* if no digit is after '-', it's wrong*/
if (at_start && in_range)
return -EINVAL;
- if (!(a <= b) || !(used_size <= group_size))
+ if (!(a <= b) || group_size == 0 || !(used_size <= group_size))
return -EINVAL;
if (b >= nmaskbits)
return -ERANGE;
diff -puN lib/test_bitmap.c~lib-fix-stall-in-__bitmap_parselist lib/test_bitmap.c
--- a/lib/test_bitmap.c~lib-fix-stall-in-__bitmap_parselist
+++ a/lib/test_bitmap.c
@@ -255,6 +255,10 @@ static const struct test_bitmap_parselis
{-EINVAL, "-1", NULL, 8, 0},
{-EINVAL, "-0", NULL, 8, 0},
{-EINVAL, "10-1", NULL, 8, 0},
+ {-EINVAL, "0-31:", NULL, 8, 0},
+ {-EINVAL, "0-31:0", NULL, 8, 0},
+ {-EINVAL, "0-31:0/0", NULL, 8, 0},
+ {-EINVAL, "0-31:1/0", NULL, 8, 0},
{-EINVAL, "0-31:10/1", NULL, 8, 0},
};
_
Patches currently in -mm which might be from ynorov(a)caviumnetworks.com are
lib-fix-stall-in-__bitmap_parselist.patch
This patch orders getting budget and driver tag by making sure to acquire
driver tag after budget is got, this way can help to avoid the following
race:
1) before dispatch request from scheduler queue, get one budget first, then
dequeue a request, call it request A.
2) in another IO path for dispatching request B which is from hctx->dispatch,
driver tag is got, then try to get budget in blk_mq_dispatch_rq_list(),
unfortunately the budget is held by request A.
3) meantime blk_mq_dispatch_rq_list() is called for dispatching request
A, and try to get driver tag first, unfortunately no driver tag is
available because the driver tag is held by request B
4) both two IO pathes can't move on, and IO stall is caused.
This issue can be observed when running dbench on USB storage.
This patch fixes this issue by always getting budget before getting
driver tag.
Cc: stable(a)vger.kernel.org
Fixes: de1482974080ec9e ("blk-mq: introduce .get_budget and .put_budget in blk_mq_ops")
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: Bart Van Assche <bart.vanassche(a)wdc.com>
Cc: Omar Sandoval <osandov(a)fb.com>
Signed-off-by: Ming Lei <ming.lei(a)redhat.com>
---
block/blk-mq.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 16e83e6df404..90838e998f66 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1188,7 +1188,12 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
struct blk_mq_queue_data bd;
rq = list_first_entry(list, struct request, queuelist);
- if (!blk_mq_get_driver_tag(rq, &hctx, false)) {
+
+ hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
+ if (!got_budget && !blk_mq_get_dispatch_budget(hctx))
+ break;
+
+ if (!blk_mq_get_driver_tag(rq, NULL, false)) {
/*
* The initial allocation attempt failed, so we need to
* rerun the hardware queue when a tag is freed. The
@@ -1197,8 +1202,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
* we'll re-run it below.
*/
if (!blk_mq_mark_tag_wait(&hctx, rq)) {
- if (got_budget)
- blk_mq_put_dispatch_budget(hctx);
+ blk_mq_put_dispatch_budget(hctx);
/*
* For non-shared tags, the RESTART check
* will suffice.
@@ -1209,11 +1213,6 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
}
}
- if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) {
- blk_mq_put_driver_tag(rq);
- break;
- }
-
list_del_init(&rq->queuelist);
bd.rq = rq;
@@ -1812,11 +1811,11 @@ static blk_status_t __blk_mq_try_issue_directly(struct blk_mq_hw_ctx *hctx,
if (q->elevator && !bypass_insert)
goto insert;
- if (!blk_mq_get_driver_tag(rq, NULL, false))
+ if (!blk_mq_get_dispatch_budget(hctx))
goto insert;
- if (!blk_mq_get_dispatch_budget(hctx)) {
- blk_mq_put_driver_tag(rq);
+ if (!blk_mq_get_driver_tag(rq, NULL, false)) {
+ blk_mq_put_dispatch_budget(hctx);
goto insert;
}
--
2.9.5
While enabling/disabling DPMS before link training with MST hubs is
perfectly valid; unfortunately disabling DPMS results in some devices
disabling their AUX CH block as well. For SST this isn't as much of a
problem, but for MST we need to be able to continue handling aux
transactions even when none of the sinks are turned on since it's
possible for us to have a single atomic commit which results in
disabling each downstream sink, followed by subsequently re-enabling
each sink.
If we don't do this, we'll end up stalling any pending ESI interrupts
from the sink for up to 1ms. Unfortunately, dropping ESIs during this
timespan makes it so that link fallback retraining for MST (which I will
be submitting to the ML shortly) fails due to the channel EQ failure
interrupts potentially getting dropped. Additionally, when performing a
modeset that brings the hub status's link status from bad -> good having
ESIs disabled for that long causes us to miss the hub's response to us
trying to start link training as well.
Since any sink with MST is going to support DisplayPort 1.2 anyway, save
us the hassle of trying to wait until the sink comes back up and just
never shut the aux block down.
Changes since v2:
- Fix patch name, no functional changes
Changes since v3:
- acks, t-b's
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Acked-by: Dhinakaran Pandiyan <dhinakaran.pandiyan(a)intel.com>
Tested-by: Laura Abbott <labbott(a)redhat.com>
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Cc: stable(a)vger.kernel.org
Fixes: ad260ab32a4d9 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.")
---
drivers/gpu/drm/i915/intel_dp.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 62f82c4298ac..0479c377981b 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2589,11 +2589,13 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode)
return;
if (mode != DRM_MODE_DPMS_ON) {
+ unsigned char data = intel_dp->is_mst ?
+ DP_SET_POWER_D3_AUX_ON : DP_SET_POWER_D3;
+
if (downstream_hpd_needs_d0(intel_dp))
return;
- ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER,
- DP_SET_POWER_D3);
+ ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, data);
} else {
struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp);
--
2.14.3
While enabling/disabling DPMS before link training with MST hubs is
perfectly valid; unfortunately disabling DPMS results in some devices
disabling their AUX CH block as well. For SST this isn't as much of a
problem, but for MST we need to be able to continue handling aux
transactions even when none of the sinks are turned on since it's
possible for us to have a single atomic commit which results in
disabling each downstream sink, followed by subsequently re-enabling
each sink.
If we don't do this, we'll end up stalling any pending ESI interrupts
from the sink for up to 1ms. Unfortunately, dropping ESIs during this
timespan makes it so that link fallback retraining for MST (which I will
be submitting to the ML shortly) fails due to the channel EQ failure
interrupts potentially getting dropped. Additionally, when performing a
modeset that brings the hub status's link status from bad -> good having
ESIs disabled for that long causes us to miss the hub's response to us
trying to start link training as well.
Since any sink with MST is going to support DisplayPort 1.2 anyway, save
us the hassle of trying to wait until the sink comes back up and just
never shut the aux block down.
Changes since v2:
- Fix patch name, no functional changes
Signed-off-by: Lyude Paul <lyude(a)redhat.com>
Cc: Laura Abbott <labbott(a)redhat.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan(a)intel.com>
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Cc: stable(a)vger.kernel.org
Fixes: ad260ab32a4d9 ("drm/i915/dp: Write to SET_POWER dpcd to enable MST hub.")
---
drivers/gpu/drm/i915/intel_dp.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 62f82c4298ac..0479c377981b 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -2589,11 +2589,13 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode)
return;
if (mode != DRM_MODE_DPMS_ON) {
+ unsigned char data = intel_dp->is_mst ?
+ DP_SET_POWER_D3_AUX_ON : DP_SET_POWER_D3;
+
if (downstream_hpd_needs_d0(intel_dp))
return;
- ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER,
- DP_SET_POWER_D3);
+ ret = drm_dp_dpcd_writeb(&intel_dp->aux, DP_SET_POWER, data);
} else {
struct intel_lspcon *lspcon = dp_to_lspcon(intel_dp);
--
2.14.3
The description of commit e39a97353e53 is wrong: it mentions that
commit 2a842acab109 introduced a bug in __scsi_error_from_host_byte()
although that commit did not change the behavior of that function.
Additionally, that commit introduced a severe bug: it causes commands
that fail with hostbyte=DID_OK and driverbyte=DRIVER_SENSE to be
completed with BLK_STS_OK. Although that commit claims to fix a bug
it does not mention which bug it fixes. Hence revert that commit.
Fixes: e39a97353e53 ("scsi: core: return BLK_STS_OK for DID_OK in __scsi_error_from_host_byte()")
Reported-by: Damien Le Moal <damien.lemoal(a)wdc.com>
Signed-off-by: Bart Van Assche <bart.vanassche(a)wdc.com>
Cc: Hannes Reinecke <hare(a)suse.com>
Cc: Douglas Gilbert <dgilbert(a)interlog.com>
Cc: Damien Le Moal <damien.lemoal(a)wdc.com>
Cc: Christoph Hellwig <hch(a)lst.de>
Cc: stable(a)vger.kernel.org
---
drivers/scsi/scsi_lib.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 74a39db57d49..71f5b010684c 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -735,8 +735,6 @@ static blk_status_t __scsi_error_from_host_byte(struct scsi_cmnd *cmd,
int result)
{
switch (host_byte(result)) {
- case DID_OK:
- return BLK_STS_OK;
case DID_TRANSPORT_FAILFAST:
return BLK_STS_TRANSPORT;
case DID_TARGET_FAILURE:
--
2.16.2