From: Xingui Yang yangxingui@huawei.com
[ Upstream commit 71fb36b5ff113a7674710b9d6063241eada84ff7 ]
When freeing slots in function slot_complete_v3_hw(), it is possible that sas_dev.list is being traversed elsewhere, and it may trigger a NULL pointer exception, such as follows:
==>cq thread ==>scsi_eh_6
==>scsi_error_handler() ==>sas_eh_handle_sas_errors() ==>sas_scsi_find_task() ==>lldd_abort_task() ==>slot_complete_v3_hw() ==>hisi_sas_abort_task() ==>hisi_sas_slot_task_free() ==>dereg_device_v3_hw() ==>list_del_init() ==>list_for_each_entry_safe()
[ 7165.434918] sas: Enter sas_scsi_recover_host busy: 32 failed: 32 [ 7165.434926] sas: trying to find task 0x00000000769b5ba5 [ 7165.434927] sas: sas_scsi_find_task: aborting task 0x00000000769b5ba5 [ 7165.434940] hisi_sas_v3_hw 0000:b4:02.0: slot complete: task(00000000769b5ba5) aborted [ 7165.434964] hisi_sas_v3_hw 0000:b4:02.0: slot complete: task(00000000c9f7aa07) ignored [ 7165.434965] hisi_sas_v3_hw 0000:b4:02.0: slot complete: task(00000000e2a1cf01) ignored [ 7165.434968] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 7165.434972] hisi_sas_v3_hw 0000:b4:02.0: slot complete: task(0000000022d52d93) ignored [ 7165.434975] hisi_sas_v3_hw 0000:b4:02.0: slot complete: task(0000000066a7516c) ignored [ 7165.434976] Mem abort info: [ 7165.434982] ESR = 0x96000004 [ 7165.434991] Exception class = DABT (current EL), IL = 32 bits [ 7165.434992] SET = 0, FnV = 0 [ 7165.434993] EA = 0, S1PTW = 0 [ 7165.434994] Data abort info: [ 7165.434994] ISV = 0, ISS = 0x00000004 [ 7165.434995] CM = 0, WnR = 0 [ 7165.434997] user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000f29543f2 [ 7165.434998] [0000000000000000] pgd=0000000000000000 [ 7165.435003] Internal error: Oops: 96000004 [#1] SMP [ 7165.439863] Process scsi_eh_6 (pid: 4109, stack limit = 0x00000000c43818d5) [ 7165.468862] pstate: 00c00009 (nzcv daif +PAN +UAO) [ 7165.473637] pc : dereg_device_v3_hw+0x68/0xa8 [hisi_sas_v3_hw] [ 7165.479443] lr : dereg_device_v3_hw+0x2c/0xa8 [hisi_sas_v3_hw] [ 7165.485247] sp : ffff00001d623bc0 [ 7165.488546] x29: ffff00001d623bc0 x28: ffffa027d03b9508 [ 7165.493835] x27: ffff80278ed50af0 x26: ffffa027dd31e0a8 [ 7165.499123] x25: ffffa027d9b27f88 x24: ffffa027d9b209f8 [ 7165.504411] x23: ffffa027c45b0d60 x22: ffff80278ec07c00 [ 7165.509700] x21: 0000000000000008 x20: ffffa027d9b209f8 [ 7165.514988] x19: ffffa027d9b27f88 x18: ffffffffffffffff [ 7165.520276] x17: 0000000000000000 x16: 0000000000000000 [ 7165.525564] x15: ffff0000091d9708 x14: ffff0000093b7dc8 [ 7165.530852] x13: ffff0000093b7a23 x12: 6e7265746e692067 [ 7165.536140] x11: 0000000000000000 x10: 0000000000000bb0 [ 7165.541429] x9 : ffff00001d6238f0 x8 : ffffa027d877af00 [ 7165.546718] x7 : ffffa027d6329600 x6 : ffff7e809f58ca00 [ 7165.552006] x5 : 0000000000001f8a x4 : 000000000000088e [ 7165.557295] x3 : ffffa027d9b27fa8 x2 : 0000000000000000 [ 7165.562583] x1 : 0000000000000000 x0 : 000000003000188e [ 7165.567872] Call trace: [ 7165.570309] dereg_device_v3_hw+0x68/0xa8 [hisi_sas_v3_hw] [ 7165.575775] hisi_sas_abort_task+0x248/0x358 [hisi_sas_main] [ 7165.581415] sas_eh_handle_sas_errors+0x258/0x8e0 [libsas] [ 7165.586876] sas_scsi_recover_host+0x134/0x458 [libsas] [ 7165.592082] scsi_error_handler+0xb4/0x488 [ 7165.596163] kthread+0x134/0x138 [ 7165.599380] ret_from_fork+0x10/0x18 [ 7165.602940] Code: d5033e9f b9000040 aa0103e2 eb03003f (f9400021) [ 7165.609004] kernel fault(0x1) notification starting on CPU 75 [ 7165.700728] ---[ end trace fc042cbbea224efc ]--- [ 7165.705326] Kernel panic - not syncing: Fatal exception
To fix the issue, grab sas_dev lock when traversing the members of sas_dev.list in dereg_device_v3_hw() and hisi_sas_release_tasks() to avoid concurrency of adding and deleting member. When function hisi_sas_release_tasks() calls hisi_sas_do_release_task() to free slot, the lock cannot be grabbed again in hisi_sas_slot_task_free(), then a bool parameter need_lock is added.
Signed-off-by: Xingui Yang yangxingui@huawei.com Signed-off-by: Xiang Chen chenxiang66@hisilicon.com Link: https://lore.kernel.org/r/1679283265-115066-2-git-send-email-chenxiang66@his... Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/hisi_sas/hisi_sas.h | 3 ++- drivers/scsi/hisi_sas/hisi_sas_main.c | 25 ++++++++++++++++--------- drivers/scsi/hisi_sas/hisi_sas_v1_hw.c | 2 +- drivers/scsi/hisi_sas/hisi_sas_v2_hw.c | 2 +- drivers/scsi/hisi_sas/hisi_sas_v3_hw.c | 4 +++- 5 files changed, 23 insertions(+), 13 deletions(-)
diff --git a/drivers/scsi/hisi_sas/hisi_sas.h b/drivers/scsi/hisi_sas/hisi_sas.h index 6f8a52a1b8087..423af1dc36487 100644 --- a/drivers/scsi/hisi_sas/hisi_sas.h +++ b/drivers/scsi/hisi_sas/hisi_sas.h @@ -653,7 +653,8 @@ extern void hisi_sas_phy_down(struct hisi_hba *hisi_hba, int phy_no, int rdy, extern void hisi_sas_phy_bcast(struct hisi_sas_phy *phy); extern void hisi_sas_slot_task_free(struct hisi_hba *hisi_hba, struct sas_task *task, - struct hisi_sas_slot *slot); + struct hisi_sas_slot *slot, + bool need_lock); extern void hisi_sas_init_mem(struct hisi_hba *hisi_hba); extern void hisi_sas_rst_work_handler(struct work_struct *work); extern void hisi_sas_sync_rst_work_handler(struct work_struct *work); diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c index 8c038ccf1c095..2093c1e828177 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_main.c +++ b/drivers/scsi/hisi_sas/hisi_sas_main.c @@ -205,7 +205,7 @@ static int hisi_sas_slot_index_alloc(struct hisi_hba *hisi_hba, }
void hisi_sas_slot_task_free(struct hisi_hba *hisi_hba, struct sas_task *task, - struct hisi_sas_slot *slot) + struct hisi_sas_slot *slot, bool need_lock) { int device_id = slot->device_id; struct hisi_sas_device *sas_dev = &hisi_hba->devices[device_id]; @@ -239,9 +239,13 @@ void hisi_sas_slot_task_free(struct hisi_hba *hisi_hba, struct sas_task *task, } }
- spin_lock(&sas_dev->lock); - list_del_init(&slot->entry); - spin_unlock(&sas_dev->lock); + if (need_lock) { + spin_lock(&sas_dev->lock); + list_del_init(&slot->entry); + spin_unlock(&sas_dev->lock); + } else { + list_del_init(&slot->entry); + }
memset(slot, 0, offsetof(struct hisi_sas_slot, buf));
@@ -1021,7 +1025,7 @@ static void hisi_sas_port_notify_formed(struct asd_sas_phy *sas_phy) }
static void hisi_sas_do_release_task(struct hisi_hba *hisi_hba, struct sas_task *task, - struct hisi_sas_slot *slot) + struct hisi_sas_slot *slot, bool need_lock) { if (task) { unsigned long flags; @@ -1038,7 +1042,7 @@ static void hisi_sas_do_release_task(struct hisi_hba *hisi_hba, struct sas_task spin_unlock_irqrestore(&task->task_state_lock, flags); }
- hisi_sas_slot_task_free(hisi_hba, task, slot); + hisi_sas_slot_task_free(hisi_hba, task, slot, need_lock); }
static void hisi_sas_release_task(struct hisi_hba *hisi_hba, @@ -1047,8 +1051,11 @@ static void hisi_sas_release_task(struct hisi_hba *hisi_hba, struct hisi_sas_slot *slot, *slot2; struct hisi_sas_device *sas_dev = device->lldd_dev;
+ spin_lock(&sas_dev->lock); list_for_each_entry_safe(slot, slot2, &sas_dev->list, entry) - hisi_sas_do_release_task(hisi_hba, slot->task, slot); + hisi_sas_do_release_task(hisi_hba, slot->task, slot, false); + + spin_unlock(&sas_dev->lock); }
void hisi_sas_release_tasks(struct hisi_hba *hisi_hba) @@ -1574,7 +1581,7 @@ static int hisi_sas_abort_task(struct sas_task *task) */ if (rc == TMF_RESP_FUNC_COMPLETE && rc2 != TMF_RESP_FUNC_SUCC) { if (task->lldd_task) - hisi_sas_do_release_task(hisi_hba, task, slot); + hisi_sas_do_release_task(hisi_hba, task, slot, true); } } else if (task->task_proto & SAS_PROTOCOL_SATA || task->task_proto & SAS_PROTOCOL_STP) { @@ -1594,7 +1601,7 @@ static int hisi_sas_abort_task(struct sas_task *task) */ if ((sas_dev->dev_status == HISI_SAS_DEV_NCQ_ERR) && qc && qc->scsicmd) { - hisi_sas_do_release_task(hisi_hba, task, slot); + hisi_sas_do_release_task(hisi_hba, task, slot, true); rc = TMF_RESP_FUNC_COMPLETE; } else { rc = hisi_sas_softreset_ata_disk(device); diff --git a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c index 70c24377c6a19..76176b1fc035d 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v1_hw.c @@ -1310,7 +1310,7 @@ static void slot_complete_v1_hw(struct hisi_hba *hisi_hba, }
out: - hisi_sas_slot_task_free(hisi_hba, task, slot); + hisi_sas_slot_task_free(hisi_hba, task, slot, true);
if (task->task_done) task->task_done(task); diff --git a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c index 02575d81afca2..746e4d77de04a 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v2_hw.c @@ -2466,7 +2466,7 @@ static void slot_complete_v2_hw(struct hisi_hba *hisi_hba, } task->task_state_flags |= SAS_TASK_STATE_DONE; spin_unlock_irqrestore(&task->task_state_lock, flags); - hisi_sas_slot_task_free(hisi_hba, task, slot); + hisi_sas_slot_task_free(hisi_hba, task, slot, true);
if (!is_internal && (task->task_proto != SAS_PROTOCOL_SMP)) { spin_lock_irqsave(&device->done_lock, flags); diff --git a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c index 9afc23e3a80fc..71820a1170b4f 100644 --- a/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c +++ b/drivers/scsi/hisi_sas/hisi_sas_v3_hw.c @@ -883,6 +883,7 @@ static void dereg_device_v3_hw(struct hisi_hba *hisi_hba,
cfg_abt_set_query_iptt = hisi_sas_read32(hisi_hba, CFG_ABT_SET_QUERY_IPTT); + spin_lock(&sas_dev->lock); list_for_each_entry_safe(slot, slot2, &sas_dev->list, entry) { cfg_abt_set_query_iptt &= ~CFG_SET_ABORTED_IPTT_MSK; cfg_abt_set_query_iptt |= (1 << CFG_SET_ABORTED_EN_OFF) | @@ -890,6 +891,7 @@ static void dereg_device_v3_hw(struct hisi_hba *hisi_hba, hisi_sas_write32(hisi_hba, CFG_ABT_SET_QUERY_IPTT, cfg_abt_set_query_iptt); } + spin_unlock(&sas_dev->lock); cfg_abt_set_query_iptt &= ~(1 << CFG_SET_ABORTED_EN_OFF); hisi_sas_write32(hisi_hba, CFG_ABT_SET_QUERY_IPTT, cfg_abt_set_query_iptt); @@ -2378,7 +2380,7 @@ static void slot_complete_v3_hw(struct hisi_hba *hisi_hba, } task->task_state_flags |= SAS_TASK_STATE_DONE; spin_unlock_irqrestore(&task->task_state_lock, flags); - hisi_sas_slot_task_free(hisi_hba, task, slot); + hisi_sas_slot_task_free(hisi_hba, task, slot, true);
if (!is_internal && (task->task_proto != SAS_PROTOCOL_SMP)) { spin_lock_irqsave(&device->done_lock, flags);