From: Can Guo cang@codeaurora.org

[ Upstream commit da3fecb0040324c08f1587e5bff1f15f36be1872 ]

The scsi_block_reqs_cnt increased in ufshcd_hold() is supposed to be decreased back in ufshcd_ungate_work() in a paired way. However, if specific ufshcd_hold/release sequences are met, it is possible that scsi_block_reqs_cnt is increased twice but only one ungate work is queued. To make sure scsi_block_reqs_cnt is handled by ufshcd_hold() and ufshcd_ungate_work() in a paired way, increase it only if queue_work() returns true.

Link: https://lore.kernel.org/r/1604384682-15837-2-git-send-email-cang@codeaurora.... Reviewed-by: Hongwu Su hongwus@codeaurora.org Reviewed-by: Stanley Chu stanley.chu@mediatek.com Reviewed-by: Bean Huo beanhuo@micron.com Signed-off-by: Can Guo cang@codeaurora.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/ufs/ufshcd.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index b2cbdd01ab10b..a63119c35fde8 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -1592,12 +1592,12 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) * work and to enable clocks. */ case CLKS_OFF: - ufshcd_scsi_block_requests(hba); hba->clk_gating.state = REQ_CLKS_ON; trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); - queue_work(hba->clk_gating.clk_gating_workq, - &hba->clk_gating.ungate_work); + if (queue_work(hba->clk_gating.clk_gating_workq, + &hba->clk_gating.ungate_work)) + ufshcd_scsi_block_requests(hba); /* * fall through to check if we should wait for this * work to be done or not.

From: Hans de Goede hdegoede@redhat.com

[ Upstream commit 7daaa06357bf7f1874b62bb1ea9d66a51d4e567e ]

The Medion Akoya E2228T's ACPI _LID implementation is quite broken, it has the same issues as the one from the Medion Akoya E2215T:

1. For notifications it uses an ActiveLow Edge GpioInt, rather then an ActiveBoth one, meaning that the device is only notified when the lid is closed, not when it is opened.

2. Matching with this its _LID method simply always returns 0 (closed)

In order for the Linux LID code to work properly with this implementation, the lid_init_state selection needs to be set to ACPI_BUTTON_LID_INIT_OPEN, add a DMI quirk for this.

While working on this I also found out that the MD60### part of the model number differs per country/batch while all of the E2215T and E2228T models have this issue, so also remove the " MD60198" part from the E2215T quirk.

Signed-off-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/button.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c index f43f5adc21b61..abf101451c929 100644 --- a/drivers/acpi/button.c +++ b/drivers/acpi/button.c @@ -98,7 +98,18 @@ static const struct dmi_system_id lid_blacklst[] = { */ .matches = { DMI_MATCH(DMI_SYS_VENDOR, "MEDION"), - DMI_MATCH(DMI_PRODUCT_NAME, "E2215T MD60198"), + DMI_MATCH(DMI_PRODUCT_NAME, "E2215T"), + }, + .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, + }, + { + /* + * Medion Akoya E2228T, notification of the LID device only + * happens on close, not on open and _LID always returns closed. + */ + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "MEDION"), + DMI_MATCH(DMI_PRODUCT_NAME, "E2228T"), }, .driver_data = (void *)(long)ACPI_BUTTON_LID_INIT_OPEN, },

From: "Darrick J. Wong" darrick.wong@oracle.com

[ Upstream commit 22843291efc986ce7722610073fcf85a39b4cb13 ]

__sb_start_write has some weird looking lockdep code that claims to exist to handle nested freeze locking requests from xfs. The code as written seems broken -- if we think we hold a read lock on any of the higher freeze levels (e.g. we hold SB_FREEZE_WRITE and are trying to lock SB_FREEZE_PAGEFAULT), it converts a blocking lock attempt into a trylock.

However, it's not correct to downgrade a blocking lock attempt to a trylock unless the downgrading code or the callers are prepared to deal with that situation. Neither __sb_start_write nor its callers handle this at all. For example:

sb_start_pagefault ignores the return value completely, with the result that if xfs_filemap_fault loses a race with a different thread trying to fsfreeze, it will proceed without pagefault freeze protection (thereby breaking locking rules) and then unlocks the pagefault freeze lock that it doesn't own on its way out (thereby corrupting the lock state), which leads to a system hang shortly afterwards.

Normally, this won't happen because our ownership of a read lock on a higher freeze protection level blocks fsfreeze from grabbing a write lock on that higher level. *However*, if lockdep is offline, lock_is_held_type unconditionally returns 1, which means that percpu_rwsem_is_held returns 1, which means that __sb_start_write unconditionally converts blocking freeze lock attempts into trylocks, even when we *don't* hold anything that would block a fsfreeze.

Apparently this all held together until 5.10-rc1, when bugs in lockdep caused lockdep to shut itself off early in an fstests run, and once fstests gets to the "race writes with freezer" tests, kaboom. This might explain the long trail of vanishingly infrequent livelocks in fstests after lockdep goes offline that I've never been able to diagnose.

We could fix it by spinning on the trylock if wait==true, but AFAICT the locking works fine if lockdep is not built at all (and I didn't see any complaints running fstests overnight), so remove this snippet entirely.

NOTE: Commit f4b554af9931 in 2015 created the current weird logic (which used to exist in a different form in commit 5accdf82ba25c from 2012) in __sb_start_write. XFS solved this whole problem in the late 2.6 era by creating a variant of transactions (XFS_TRANS_NO_WRITECOUNT) that don't grab intwrite freeze protection, thus making lockdep's solution unnecessary. The commit claims that Dave Chinner explained that the trylock hack + comment could be removed, but nobody ever did.

Signed-off-by: Darrick J. Wong darrick.wong@oracle.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Jan Kara jack@suse.cz Signed-off-by: Sasha Levin sashal@kernel.org --- fs/super.c | 33 ++++----------------------------- 1 file changed, 4 insertions(+), 29 deletions(-)

diff --git a/fs/super.c b/fs/super.c index f3a8c008e1643..9fb4553c46e63 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1360,36 +1360,11 @@ EXPORT_SYMBOL(__sb_end_write); */ int __sb_start_write(struct super_block *sb, int level, bool wait) { - bool force_trylock = false; - int ret = 1; + if (!wait) + return percpu_down_read_trylock(sb->s_writers.rw_sem + level-1);

-#ifdef CONFIG_LOCKDEP - /* - * We want lockdep to tell us about possible deadlocks with freezing - * but it's it bit tricky to properly instrument it. Getting a freeze - * protection works as getting a read lock but there are subtle - * problems. XFS for example gets freeze protection on internal level - * twice in some cases, which is OK only because we already hold a - * freeze protection also on higher level. Due to these cases we have - * to use wait == F (trylock mode) which must not fail. - */ - if (wait) { - int i; - - for (i = 0; i < level - 1; i++) - if (percpu_rwsem_is_held(sb->s_writers.rw_sem + i)) { - force_trylock = true; - break; - } - } -#endif - if (wait && !force_trylock) - percpu_down_read(sb->s_writers.rw_sem + level-1); - else - ret = percpu_down_read_trylock(sb->s_writers.rw_sem + level-1); - - WARN_ON(force_trylock && !ret); - return ret; + percpu_down_read(sb->s_writers.rw_sem + level-1); + return 1; } EXPORT_SYMBOL(__sb_start_write);