6.8-stable review patch. If anyone has any objections, please let me know.
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From: Damien Le Moal dlemoal@kernel.org
commit 0c76106cb97548810214def8ee22700bbbb90543 upstream.
Commit 3cc2ffe5c16d ("scsi: sd: Differentiate system and runtime start/stop management") introduced the manage_system_start_stop scsi_device flag to allow libata to indicate to the SCSI disk driver that nothing should be done when resuming a disk on system resume. This change turned the execution of sd_resume() into a no-op for ATA devices on system resume. While this solved deadlock issues during device resume, this change also wrongly removed the execution of opal_unlock_from_suspend(). As a result, devices with TCG OPAL locking enabled remain locked and inaccessible after a system resume from sleep.
To fix this issue, introduce the SCSI driver resume method and implement it with the sd_resume() function calling opal_unlock_from_suspend(). The former sd_resume() function is renamed to sd_resume_common() and modified to call the new sd_resume() function. For non-ATA devices, this result in no functional changes.
In order for libata to explicitly execute sd_resume() when a device is resumed during system restart, the function scsi_resume_device() is introduced. libata calls this function from the revalidation work executed on devie resume, a state that is indicated with the new device flag ATA_DFLAG_RESUMING. Doing so, locked TCG OPAL enabled devices are unlocked on resume, allowing normal operation.
Fixes: 3cc2ffe5c16d ("scsi: sd: Differentiate system and runtime start/stop management") Link: https://bugzilla.kernel.org/show_bug.cgi?id=218538 Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal dlemoal@kernel.org Link: https://lore.kernel.org/r/20240319071209.1179257-1-dlemoal@kernel.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/ata/libata-eh.c | 5 ++++- drivers/ata/libata-scsi.c | 9 +++++++++ drivers/scsi/scsi_scan.c | 34 ++++++++++++++++++++++++++++++++++ drivers/scsi/sd.c | 23 +++++++++++++++++++---- include/linux/libata.h | 1 + include/scsi/scsi_driver.h | 1 + include/scsi/scsi_host.h | 1 + 7 files changed, 69 insertions(+), 5 deletions(-)
--- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -712,8 +712,10 @@ void ata_scsi_port_error_handler(struct ehc->saved_ncq_enabled |= 1 << devno;
/* If we are resuming, wake up the device */ - if (ap->pflags & ATA_PFLAG_RESUMING) + if (ap->pflags & ATA_PFLAG_RESUMING) { + dev->flags |= ATA_DFLAG_RESUMING; ehc->i.dev_action[devno] |= ATA_EH_SET_ACTIVE; + } } }
@@ -3169,6 +3171,7 @@ static int ata_eh_revalidate_and_attach( return 0;
err: + dev->flags &= ~ATA_DFLAG_RESUMING; *r_failed_dev = dev; return rc; } --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -4730,6 +4730,7 @@ void ata_scsi_dev_rescan(struct work_str struct ata_link *link; struct ata_device *dev; unsigned long flags; + bool do_resume; int ret = 0;
mutex_lock(&ap->scsi_scan_mutex); @@ -4751,7 +4752,15 @@ void ata_scsi_dev_rescan(struct work_str if (scsi_device_get(sdev)) continue;
+ do_resume = dev->flags & ATA_DFLAG_RESUMING; + spin_unlock_irqrestore(ap->lock, flags); + if (do_resume) { + ret = scsi_resume_device(sdev); + if (ret == -EWOULDBLOCK) + goto unlock; + dev->flags &= ~ATA_DFLAG_RESUMING; + } ret = scsi_rescan_device(sdev); scsi_device_put(sdev); spin_lock_irqsave(ap->lock, flags); --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -1619,6 +1619,40 @@ int scsi_add_device(struct Scsi_Host *ho } EXPORT_SYMBOL(scsi_add_device);
+int scsi_resume_device(struct scsi_device *sdev) +{ + struct device *dev = &sdev->sdev_gendev; + int ret = 0; + + device_lock(dev); + + /* + * Bail out if the device or its queue are not running. Otherwise, + * the rescan may block waiting for commands to be executed, with us + * holding the device lock. This can result in a potential deadlock + * in the power management core code when system resume is on-going. + */ + if (sdev->sdev_state != SDEV_RUNNING || + blk_queue_pm_only(sdev->request_queue)) { + ret = -EWOULDBLOCK; + goto unlock; + } + + if (dev->driver && try_module_get(dev->driver->owner)) { + struct scsi_driver *drv = to_scsi_driver(dev->driver); + + if (drv->resume) + ret = drv->resume(dev); + module_put(dev->driver->owner); + } + +unlock: + device_unlock(dev); + + return ret; +} +EXPORT_SYMBOL(scsi_resume_device); + int scsi_rescan_device(struct scsi_device *sdev) { struct device *dev = &sdev->sdev_gendev; --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -3945,7 +3945,21 @@ static int sd_suspend_runtime(struct dev return sd_suspend_common(dev, true); }
-static int sd_resume(struct device *dev, bool runtime) +static int sd_resume(struct device *dev) +{ + struct scsi_disk *sdkp = dev_get_drvdata(dev); + + sd_printk(KERN_NOTICE, sdkp, "Starting disk\n"); + + if (opal_unlock_from_suspend(sdkp->opal_dev)) { + sd_printk(KERN_NOTICE, sdkp, "OPAL unlock failed\n"); + return -EIO; + } + + return 0; +} + +static int sd_resume_common(struct device *dev, bool runtime) { struct scsi_disk *sdkp = dev_get_drvdata(dev); int ret; @@ -3961,7 +3975,7 @@ static int sd_resume(struct device *dev, sd_printk(KERN_NOTICE, sdkp, "Starting disk\n"); ret = sd_start_stop_device(sdkp, 1); if (!ret) { - opal_unlock_from_suspend(sdkp->opal_dev); + sd_resume(dev); sdkp->suspended = false; }
@@ -3980,7 +3994,7 @@ static int sd_resume_system(struct devic return 0; }
- return sd_resume(dev, false); + return sd_resume_common(dev, false); }
static int sd_resume_runtime(struct device *dev) @@ -4007,7 +4021,7 @@ static int sd_resume_runtime(struct devi "Failed to clear sense data\n"); }
- return sd_resume(dev, true); + return sd_resume_common(dev, true); }
static const struct dev_pm_ops sd_pm_ops = { @@ -4030,6 +4044,7 @@ static struct scsi_driver sd_template = .pm = &sd_pm_ops, }, .rescan = sd_rescan, + .resume = sd_resume, .init_command = sd_init_command, .uninit_command = sd_uninit_command, .done = sd_done, --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -107,6 +107,7 @@ enum {
ATA_DFLAG_NCQ_PRIO_ENABLED = (1 << 20), /* Priority cmds sent to dev */ ATA_DFLAG_CDL_ENABLED = (1 << 21), /* cmd duration limits is enabled */ + ATA_DFLAG_RESUMING = (1 << 22), /* Device is resuming */ ATA_DFLAG_DETACH = (1 << 24), ATA_DFLAG_DETACHED = (1 << 25), ATA_DFLAG_DA = (1 << 26), /* device supports Device Attention */ --- a/include/scsi/scsi_driver.h +++ b/include/scsi/scsi_driver.h @@ -12,6 +12,7 @@ struct request; struct scsi_driver { struct device_driver gendrv;
+ int (*resume)(struct device *); void (*rescan)(struct device *); blk_status_t (*init_command)(struct scsi_cmnd *); void (*uninit_command)(struct scsi_cmnd *); --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -767,6 +767,7 @@ scsi_template_proc_dir(const struct scsi #define scsi_template_proc_dir(sht) NULL #endif extern void scsi_scan_host(struct Scsi_Host *); +extern int scsi_resume_device(struct scsi_device *sdev); extern int scsi_rescan_device(struct scsi_device *sdev); extern void scsi_remove_host(struct Scsi_Host *); extern struct Scsi_Host *scsi_host_get(struct Scsi_Host *);