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sg_finish_rem_req() calls blk_rq_unmap_user(). The latter function may
sleep. Hence, call sg_finish_rem_req() with interrupts enabled instead
of disabled.
Reported-by: syzbot+c01f8e6e73f20459912e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-scsi/691560c4.a70a0220.3124cb.001a.GAE@google.com/
Cc: Hannes Reinecke <hare@suse.de>
Cc: stable@vger.kernel.org
Fixes: 97d27b0dd015 ("scsi: sg: close race condition in sg_remove_sfp_usercontext()")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251113181643.1108973-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If the allocation of tl_hba->sh fails in tcm_loop_driver_probe() and we
attempt to dereference it in tcm_loop_tpg_address_show() we will get a
segfault, see below for an example. So, check tl_hba->sh before
dereferencing it.
Unable to allocate struct scsi_host
BUG: kernel NULL pointer dereference, address: 0000000000000194
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 8356 Comm: tokio-runtime-w Not tainted 6.6.104.2-4.azl3 #1
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 09/28/2024
RIP: 0010:tcm_loop_tpg_address_show+0x2e/0x50 [tcm_loop]
...
Call Trace:
<TASK>
configfs_read_iter+0x12d/0x1d0 [configfs]
vfs_read+0x1b5/0x300
ksys_read+0x6f/0xf0
...
Cc: stable@vger.kernel.org
Fixes: 2628b352c3d4 ("tcm_loop: Show address of tpg in configfs")
Signed-off-by: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Allen Pais <apais@linux.microsoft.com>
Link: https://patch.msgid.link/1762370746-6304-1-git-send-email-hamzamahfooz@linux.microsoft.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
After DME Link Startup, the error return value is set to the MIPI UniPro
GenericErrorCode which can be 0 (SUCCESS) or 1 (FAILURE). Upon failure
during driver probe, the error code 1 is propagated back to the driver
probe function which must return a negative value to indicate an error,
but 1 is not negative, so the probe is considered to be successful even
though it failed. Subsequently, removing the driver results in an oops
because it is not in a valid state.
This happens because none of the callers of ufshcd_init() expect a
non-negative error code.
Fix the return value and documentation to match actual usage.
Fixes: 69f5eb78d4b0 ("scsi: ufs: core: Move the ufshcd_device_init(hba, true) call")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251024085918.31825-5-adrian.hunter@intel.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Link startup becomes unreliable for Intel Alder Lake based host
controllers when a 2nd DME_LINKSTARTUP is issued unnecessarily. Employ
UFSHCD_QUIRK_PERFORM_LINK_STARTUP_ONCE to suppress that from happening.
Fixes: 7dc9fb47bc9a ("scsi: ufs: ufs-pci: Add support for Intel ADL")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251024085918.31825-4-adrian.hunter@intel.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
ufshcd_link_startup() has a facility (link_startup_again) to issue
DME_LINKSTARTUP a 2nd time even though the 1st time was successful.
Some older hardware benefits from that, however the behaviour is
non-standard, and has been found to cause link startup to be unreliable
for some Intel Alder Lake based host controllers.
Add UFSHCD_QUIRK_PERFORM_LINK_STARTUP_ONCE to suppress
link_startup_again, in preparation for setting the quirk for affected
controllers.
Fixes: 7dc9fb47bc9a ("scsi: ufs: ufs-pci: Add support for Intel ADL")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251024085918.31825-3-adrian.hunter@intel.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Intel platforms with UFS, can support Suspend-to-Idle (S0ix) and
Suspend-to-RAM (S3). For S0ix the link state should be HIBERNATE. For
S3, state is lost, so the link state must be OFF. Driver policy,
expressed by spm_lvl, can be 3 (link HIBERNATE, device SLEEP) for S0ix
but must be changed to 5 (link OFF, device POWEROFF) for S3.
Fix support for S0ix/S3 by switching spm_lvl as needed. During suspend
->prepare(), if the suspend target state is not Suspend-to-Idle, ensure
the spm_lvl is at least 5 to ensure that resume will be possible from
deep sleep states. During suspend ->complete(), restore the spm_lvl to
its original value that is suitable for S0ix.
This fix is first needed in Intel Alder Lake based controllers.
Fixes: 7dc9fb47bc9a ("scsi: ufs: ufs-pci: Add support for Intel ADL")
Cc: stable@vger.kernel.org
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251024085918.31825-2-adrian.hunter@intel.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Patch "Make HID attributes visible" is needed for older kernel versions
(e.g. 6.12) where ufs_get_device_desc() is called from ufshcd_probe_hba().
In these older kernel versions ufshcd_get_device_desc() may be called
after the sysfs attributes have been added. In the upstream kernel however
ufshcd_get_device_desc() is called before ufs_sysfs_add_nodes(). See also
the ufshcd_device_params_init() call from ufshcd_init(). Hence, calling
sysfs_update_group() is not necessary.
See also commit 69f5eb78d4b0 ("scsi: ufs: core: Move the
ufshcd_device_init(hba, true) call") in kernel v6.13.
This patch fixes the following kernel warning:
sysfs: cannot create duplicate filename '/devices/platform/3c2d0000.ufs/hid'
Workqueue: async async_run_entry_fn
Call trace:
dump_backtrace+0xfc/0x17c
show_stack+0x18/0x28
dump_stack_lvl+0x40/0x104
dump_stack+0x18/0x3c
sysfs_warn_dup+0x6c/0xc8
internal_create_group+0x1c8/0x504
sysfs_create_groups+0x38/0x9c
ufs_sysfs_add_nodes+0x20/0x58
ufshcd_init+0x1114/0x134c
ufshcd_pltfrm_init+0x728/0x7d8
ufs_google_probe+0x30/0x84
platform_probe+0xa0/0xe0
really_probe+0x114/0x454
__driver_probe_device+0xa4/0x160
driver_probe_device+0x44/0x23c
__device_attach_driver+0x15c/0x1f4
bus_for_each_drv+0x10c/0x168
__device_attach_async_helper+0x80/0xf8
async_run_entry_fn+0x4c/0x17c
process_one_work+0x26c/0x65c
worker_thread+0x33c/0x498
kthread+0x110/0x134
ret_from_fork+0x10/0x20
ufshcd 3c2d0000.ufs: ufs_sysfs_add_nodes: sysfs groups creation failed (err = -17)
Cc: Daniel Lee <chullee@google.com>
Cc: Peter Wang <peter.wang@mediatek.com>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Neil Armstrong <neil.armstrong@linaro.org>
Fixes: bb7663dec67b ("scsi: ufs: sysfs: Make HID attributes visible")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Fixes: bb7663dec67b ("scsi: ufs: sysfs: Make HID attributes visible")
Acked-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Link: https://patch.msgid.link/20251028222433.1108299-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Some systems, e.g. Rock 4D, have a pluggable UFS module. Link startup
fails systematically on these systems. If no UFS module has been plugged
in, more than fourty lines are logged after the "link startup failed"
message. Avoid this by reducing link startup failure logging.
An intended side effect of this patch is that scsi_host_busy() is not
called before scsi_add_host() is called.
Commit 995412e23bb2 ("blk-mq: Replace tags->lock with SRCU for tag
iterators") introduced a regression - the warning shown below is
triggered during every boot. This patch fixes that regression.
Call trace:
__srcu_read_lock+0x30/0x80 (P)
blk_mq_tagset_busy_iter+0x44/0x300
scsi_host_busy+0x38/0x70
ufshcd_print_host_state+0x34/0x1bc
ufshcd_link_startup.constprop.0+0xe4/0x2e0
ufshcd_init+0x944/0xf80
ufshcd_pltfrm_init+0x504/0x820
ufs_rockchip_probe+0x2c/0x88
platform_probe+0x5c/0xa4
really_probe+0xc0/0x38c
__driver_probe_device+0x7c/0x150
driver_probe_device+0x40/0x120
__driver_attach+0xc8/0x1e0
bus_for_each_dev+0x7c/0xdc
driver_attach+0x24/0x30
bus_add_driver+0x110/0x230
driver_register+0x68/0x130
__platform_driver_register+0x20/0x2c
ufs_rockchip_pltform_init+0x1c/0x28
do_one_initcall+0x60/0x1e0
kernel_init_freeable+0x248/0x2c4
kernel_init+0x20/0x140
ret_from_fork+0x10/0x20
Reported-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Closes: https://lore.kernel.org/linux-block/pnezafputodmqlpumwfbn644ohjybouveehcjhz2hmhtcf2rka@sdhoiivync4y/
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251014200118.3390839-3-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
ufs_sysfs_add_nodes() is called concurrently with ufs_get_device_desc().
This may cause the following code to be called before
ufs_sysfs_add_nodes():
sysfs_update_group(&hba->dev->kobj, &ufs_sysfs_hid_group);
If this happens, ufs_sysfs_add_nodes() triggers a kernel warning and
fails. Fix this by calling ufs_sysfs_add_nodes() before SCSI LUNs are
scanned since the sysfs_update_group() call happens from the context of
thread that executes ufshcd_async_scan(). This patch fixes the following
kernel warning:
sysfs: cannot create duplicate filename '/devices/platform/3c2d0000.ufs/hid'
Workqueue: async async_run_entry_fn
Call trace:
dump_backtrace+0xfc/0x17c
show_stack+0x18/0x28
dump_stack_lvl+0x40/0x104
dump_stack+0x18/0x3c
sysfs_warn_dup+0x6c/0xc8
internal_create_group+0x1c8/0x504
sysfs_create_groups+0x38/0x9c
ufs_sysfs_add_nodes+0x20/0x58
ufshcd_init+0x1114/0x134c
ufshcd_pltfrm_init+0x728/0x7d8
ufs_google_probe+0x30/0x84
platform_probe+0xa0/0xe0
really_probe+0x114/0x454
__driver_probe_device+0xa4/0x160
driver_probe_device+0x44/0x23c
__device_attach_driver+0x15c/0x1f4
bus_for_each_drv+0x10c/0x168
__device_attach_async_helper+0x80/0xf8
async_run_entry_fn+0x4c/0x17c
process_one_work+0x26c/0x65c
worker_thread+0x33c/0x498
kthread+0x110/0x134
ret_from_fork+0x10/0x20
ufshcd 3c2d0000.ufs: ufs_sysfs_add_nodes: sysfs groups creation failed (err = -17)
Cc: Daniel Lee <chullee@google.com>
Fixes: bb7663dec67b ("scsi: ufs: sysfs: Make HID attributes visible")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251014200118.3390839-2-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
According to UFS specifications, the power-off sequence for a UFS device
includes:
- Sending an SSU command with Power_Condition=3 and await a response.
- Asserting RST_N low.
- Turning off REF_CLK.
- Turning off VCC.
- Turning off VCCQ/VCCQ2.
As part of ufs shutdown, after the SSU command completion, asserting
hardware reset (HWRST) triggers the device firmware to wake up and
execute its reset routine. This routine initializes hardware blocks and
takes a few milliseconds to complete. During this time, the ICCQ draws a
large current.
This large ICCQ current may cause issues for the regulator which is
supplying power to UFS, because the turn off request from UFS driver to
the regulator framework will be immediately followed by low power
mode(LPM) request by regulator framework. This is done by framework
because UFS which is the only client is requesting for disable. So if
the rail is still in the process of shutting down while ICCQ exceeds LPM
current thresholds, and LPM mode is activated in hardware during this
state, it may trigger an overcurrent protection (OCP) fault in the
regulator.
To prevent this, a 10ms delay is added after asserting HWRST. This
allows the reset operation to complete while power rails remain active
and in high-power mode.
Currently there is no way for Host to query whether the reset is
completed or not and hence this the delay is based on experiments with
Qualcomm UFS controllers across multiple UFS vendors.
Signed-off-by: Nitin Rawat <nitin.rawat@oss.qualcomm.com>
Reviewed-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20251012173828.9880-1-nitin.rawat@oss.qualcomm.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
scsi_decide_disposition() may call scsi_check_sense().
scsi_decide_disposition() calls are not serialized. Hence, counter
updates by scsi_check_sense() must be serialized. Hence this patch that
makes the counters updated by scsi_check_sense() atomic.
Cc: Kai Mäkisara <Kai.Makisara@kolumbus.fi>
Fixes: a5d518cd4e3e ("scsi: core: Add counters for New Media and Power On/Reset UNIT ATTENTIONs")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Link: https://patch.msgid.link/20251014220244.3689508-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A value of an attribute will be initialized at ufshcd_dme_get_attr().
There is no need to initialize a tx_lanes.
Signed-off-by: Wonkon Kim <wkon.kim@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251020061539.28661-3-wkon.kim@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If ufshcd_send_cmd() fails, *mib_val may have a garbage value. It can
get an unintended value of an attribute.
Make ufshcd_dme_get_attr() always initialize *mib_val.
Fixes: 12b4fdb4f6bc ("[SCSI] ufs: add dme configuration primitives")
Signed-off-by: Wonkon Kim <wkon.kim@samsung.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251020061539.28661-2-wkon.kim@samsung.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Fix the issue where host_sem is not released due to a new return path in
commit f966e02ae521 ("scsi: ufs: core: Fix runtime suspend error
deadlock").
Check pm_op_in_progress before acquiring hba->host_sem to prevent
deadlocks and ensure proper resource management during error
handling. Add comment for use ufshcd_rpm_get_noresume() to safely
perform link recovery without interfering with ongoing PM operations.
Fixes: f966e02ae521 ("scsi: ufs: core: Fix runtime suspend error deadlock")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20251008065651.1589614-2-peter.wang@mediatek.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Commit 995412e23bb2 ("blk-mq: Replace tags->lock with SRCU for tag
iterators") introduced the following regression:
Call trace:
__srcu_read_lock+0x30/0x80 (P)
blk_mq_tagset_busy_iter+0x44/0x300
scsi_host_busy+0x38/0x70
ufshcd_print_host_state+0x34/0x1bc
ufshcd_link_startup.constprop.0+0xe4/0x2e0
ufshcd_init+0x944/0xf80
ufshcd_pltfrm_init+0x504/0x820
ufs_rockchip_probe+0x2c/0x88
platform_probe+0x5c/0xa4
really_probe+0xc0/0x38c
__driver_probe_device+0x7c/0x150
driver_probe_device+0x40/0x120
__driver_attach+0xc8/0x1e0
bus_for_each_dev+0x7c/0xdc
driver_attach+0x24/0x30
bus_add_driver+0x110/0x230
driver_register+0x68/0x130
__platform_driver_register+0x20/0x2c
ufs_rockchip_pltform_init+0x1c/0x28
do_one_initcall+0x60/0x1e0
kernel_init_freeable+0x248/0x2c4
kernel_init+0x20/0x140
ret_from_fork+0x10/0x20
Fix this regression by making scsi_host_busy() check whether the SCSI
host tag set has already been initialized. tag_set->ops is set by
scsi_mq_setup_tags() just before blk_mq_alloc_tag_set() is called. This
fix is based on the assumption that scsi_host_busy() and
scsi_mq_setup_tags() calls are serialized. This is the case in the UFS
driver.
Reported-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Closes: https://lore.kernel.org/linux-block/pnezafputodmqlpumwfbn644ohjybouveehcjhz2hmhtcf2rka@sdhoiivync4y/
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://patch.msgid.link/20251007214800.1678255-1-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull in outstanding SCSI fixes for 6.18.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
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