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From:   =?iso-8859-1?Q?Christian_L=F6hle?= <CLoehle@hyperstone.com>
To:     "ulf.hansson@linaro.org" <ulf.hansson@linaro.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Linux MMC List <linux-mmc@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        =?iso-8859-1?Q?Christian_L=F6hle?= <CLoehle@hyperstone.com>
CC:     Avri Altman <Avri.Altman@wdc.com>
Subject: [PATCH] mmc: core: fix race of queue reset and card removal
Thread-Topic: [PATCH] mmc: core: fix race of queue reset and card removal
Thread-Index: AdjX7pQAAXK3jl/fRweqH3RcJ0C5Tg==
Date:   Tue, 4 Oct 2022 12:42:07 +0000
Message-ID: <d3897c967cd5482f8778264708012f43@hyperstone.com>
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If a recovery is active and the card is removed do not
try to switch back partitions. Furthermore do not remove
queue card pointer as it is not sychronized with recovery.

This has been observed with recovery active with CQE.
[ 1083.510578] Unable to handle kernel NULL pointer dereference at virtual address 000000000000038c
[ 1083.511362] Mem abort info:
[ 1083.511626]   ESR = 0x96000004
[ 1083.511912]   EC = 0x25: DABT (current EL), IL = 32 bits
[ 1083.512395]   SET = 0, FnV = 0
[ 1083.512681]   EA = 0, S1PTW = 0
[ 1083.512973]   FSC = 0x04: level 0 translation fault
[ 1083.513417] Data abort info:
[ 1083.513686]   ISV = 0, ISS = 0x00000004
[ 1083.514039]   CM = 0, WnR = 0
[ 1083.514318] user pgtable: 4k pages, 48-bit VAs, pgdp=000000000a4c3000
[ 1083.514899] [000000000000038c] pgd=0000000000000000, p4d=0000000000000000
[ 1083.515854] Internal error: Oops: 96000004 [#1] SMP
[ 1083.516295] CPU: 0 PID: 153 Comm: kworker/0:2 Tainted: G        W         5.18.12-g925ff1d10c99-dirty #7
[ 1083.517127] Hardware name: Pine64 RockPro64 v2.1 (DT)
[ 1083.517574] Workqueue: events mmc_mq_recovery_handler
[ 1083.518032] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 1083.518645] pc : mmc_blk_reset+0x60/0x1ac
[ 1083.519004] lr : mmc_blk_reset+0x38/0x1ac
[ 1083.519361] sp : ffff8000100b3cd0
[ 1083.519654] x29: ffff8000100b3cd0 x28: 0000000000000000 x27: 0000000000000000
[ 1083.520288] x26: ffff80000b0ba000 x25: ffff0000f6e74805 x24: ffff000004c2fdc0
[ 1083.520922] x23: ffff000014950000 x22: ffff000004c2fc18 x21: ffff00000a33c000
[ 1083.521556] x20: 00000000ffffff85 x19: ffff000004c2fc00 x18: ffffffffffffffff
[ 1083.522189] x17: ffff80000cd9b200 x16: ffff80000cd9b190 x15: 0000000000000006
[ 1083.522823] x14: 0000000000000000 x13: ffff80000b0c28f0 x12: 0000000000001707
[ 1083.523457] x11: 00000000000007ad x10: ffff80000c6c28f0 x9 : ffff80000b0c28f0
[ 1083.524090] x8 : 00000000fffbffff x7 : 0000000000000001 x6 : 0000000000000000
[ 1083.524723] x5 : 0000000000000000 x4 : ffff0000f6e62d30 x3 : 0000000000000000
[ 1083.525357] x2 : 0000000000000000 x1 : ffff00000b6e0000 x0 : 0000000000000000
[ 1083.525990] Call trace:
[ 1083.526209]  mmc_blk_reset+0x60/0x1ac
[ 1083.526536]  mmc_blk_cqe_recovery+0x8c/0xd0
[ 1083.526908]  mmc_mq_recovery_handler+0xc4/0xd0
[ 1083.527303]  process_one_work+0x23c/0x3fc
[ 1083.527663]  worker_thread+0x74/0x420
[ 1083.527990]  kthread+0xec/0xf0
[ 1083.528264]  ret_from_fork+0x10/0x20
[ 1083.528587] Code: d50323bf d65f03c0 f94352a0 f9404000 (b9438c01)
[ 1083.529126] ---[ end trace 0000000000000000 ]---

[ 1431.677970] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 1431.678753] Mem abort info:
[ 1431.679017]   ESR = 0x96000004
[ 1431.679303]   EC = 0x25: DABT (current EL), IL = 32 bits
[ 1431.679786]   SET = 0, FnV = 0
[ 1431.680072]   EA = 0, S1PTW = 0
[ 1431.680366]   FSC = 0x04: level 0 translation fault
[ 1431.680810] Data abort info:
[ 1431.681080]   ISV = 0, ISS = 0x00000004
[ 1431.681432]   CM = 0, WnR = 0
[ 1431.681712] user pgtable: 4k pages, 48-bit VAs, pgdp=000000000bb98000
[ 1431.682390] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
[ 1431.683393] Internal error: Oops: 96000004 [#1] SMP
[ 1431.683841] CPU: 0 PID: 19948 Comm: kworker/0:2 Not tainted 5.18.12-gf65532578f32-dirty #16
[ 1431.684576] Hardware name: Pine64 RockPro64 v2.1 (DT)
[ 1431.685024] Workqueue: events mmc_mq_recovery_handler
[ 1431.685487] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 1431.686100] pc : mmc_put_card+0x38/0x110
[ 1431.686453] lr : mmc_mq_recovery_handler+0x98/0xd0
[ 1431.686879] sp : ffff800015813cf0
[ 1431.687173] x29: ffff800015813cf0 x28: 0000000000000000 x27: 0000000000000000
[ 1431.687807] x26: ffff80000b0ba000 x25: ffff0000f6e74805 x24: ffff000013bd65c0
[ 1431.688441] x23: ffff000013b96120 x22: ffff000013bd6418 x21: 0000000000000000
[ 1431.689075] x20: ffff800008ed1c70 x19: ffff8000091767d8 x18: ffffffffffffffff
[ 1431.689709] x17: 31335b1b6d375b1b x16: 6d305b1b47554245 x15: 0000000000000006
[ 1431.690343] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000
[ 1431.690976] x11: ffff000013bd6570 x10: 0000000000000001 x9 : ffff80000ea69228
[ 1431.691611] x8 : ffff80000df892c8 x7 : 0000000000000000 x6 : 0000000000000001
[ 1431.692245] x5 : 0000000000000001 x4 : 0000000000000002 x3 : ffff80000e6feac8
[ 1431.692879] x2 : 000000000000036e x1 : ffff800008ed1c70 x0 : 0000000000000000
[ 1431.693513] Call trace:
[ 1431.693732]  mmc_put_card+0x38/0x110
[ 1431.694055]  mmc_mq_recovery_handler+0x98/0xd0
[ 1431.694452]  process_one_work+0x23c/0x3fc
[ 1431.694812]  worker_thread+0x74/0x420
[ 1431.695139]  kthread+0xec/0xf0
[ 1431.695414]  ret_from_fork+0x10/0x20
[ 1431.695738] Code: f9001bf7 aa0103f6 aa0003f5 aa1403e1 (f9400017)
[ 1431.696278] ---[ end trace 0000000000000000 ]---

Signed-off-by: Christian Loehle <cloehle@hyperstone.com>
---
 drivers/mmc/core/block.c | 4 ++--
 drivers/mmc/core/queue.c | 2 --
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index ce89611a136e..0cd3a7065629 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -997,8 +997,8 @@ static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host,
 
 	md->reset_done |= type;
 	err = mmc_hw_reset(host->card);
-	/* Ensure we switch back to the correct partition */
-	if (err) {
+	/* Ensure we switch back to the correct partition on successful reset */
+	if (!err) {
 		struct mmc_blk_data *main_md =
 			dev_get_drvdata(&host->card->dev);
 		int part_err;
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index fefaa901b50f..bfd201a5d245 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -501,8 +501,6 @@ void mmc_cleanup_queue(struct mmc_queue *mq)
 	 * still be queued at this point. Flush it.
 	 */
 	flush_work(&mq->complete_work);
-
-	mq->card = NULL;
 }
 
 /*
-- 
2.37.3

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