From: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx>
With one special SD card, below divide by zero error observed:
...
[ 2.144300] divide error: 0000 [#1] PREEMPT SMP
[ 2.148860] Modules linked in:
[ 2.151898]
[ 2.152685] Set up 4031 stolen pages starting at 0x0001f000, GTT offset 0K
[ 2.157330] Set up 0 CI stolen pages starting at 0x00000000, GTT offset 131072K
[ 2.167581] Pid: 5, comm: kworker/u:0 Not tainted 3.0.8-138216-g974a2ab #1
[ 2.169506] [drm] PSB GTT mem manager ready, tt_start 4031, tt_size 28737 pages
[ 2.169906] [drm] SGX core id = 0x00000000
[ 2.169920] [drm] SGX core rev major = 0x00, minor = 0x00
[ 2.169934] [drm] SGX core rev maintenance = 0x00, designer = 0x00
[ 2.197370] Intel Corporation Medfield/iCDKB
[ 2.201716] EIP: 0060:[<c1697ca6>] EFLAGS: 00010246 CPU: 1
[ 2.207198] EIP is at mmc_init_erase+0x76/0x150
[ 2.211704] EAX: 00002000 EBX: dcd1b400 ECX: 00002000 EDX: 00000000
[ 2.217957] ESI: 00000000 EDI: dcd5c800 EBP: dd867e84 ESP: dd867e7c
[ 2.224214] DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
[ 2.229605] Process kworker/u:0 (pid: 5, ti=dd866000 task=dd868000 task.ti=dd866000)
[ 2.237325] Stack:
[ 2.239322] dcd1b400 00000000 dd867eb0 c16a06da c1ab7c44 dd995aa8 00000003 00000000
[ 2.247054] 00000000 00000000 dcd5c800 00000000 dcd1b400 dd867ef8 c16a1012 c1698b00
[ 2.254785] 00000029 00000001 c194eb80 dcd5c9ec dd867e00 c1239b00 00000000 00000000
[ 2.262519] Call Trace:
[ 2.264975] [<c16a06da>] mmc_sd_setup_card+0x1da/0x4f0
[ 2.270183] [<c16a1012>] mmc_sd_init_card+0x192/0xc40
[ 2.275304] [<c1698b00>] ? __mmc_claim_host+0x160/0x160
[ 2.280610] [<c1239b00>] ? __schedule_bug+0x50/0x80
[ 2.285556] [<c16a1b89>] mmc_attach_sd+0xc9/0x230
[ 2.290333] [<c169b6ef>] mmc_rescan+0x25f/0x2c0
[ 2.294943] [<c1274223>] process_one_work+0x103/0x400
[ 2.300065] [<c12670fd>] ? mod_timer+0x1ad/0x3c0
[ 2.304756] [<c169b490>] ? mmc_suspend_host+0x1a0/0x1a0
[ 2.310056] [<c127502d>] worker_thread+0x12d/0x4a0
[ 2.314921] [<c18fcfbd>] ? preempt_schedule+0x2d/0x50
[ 2.320047] [<c1274f00[ 2.323976] ---[ end trace 5398ec2720494438 ]---
...
So, seems this bad SD card does not set valid value in related SSR / CSD register fields.
And then the driver will set card->erase_size to 0.
Then it triggered this divided by zero error when calculate card->pref_erase.
Submit this patch to fix the issue.
Signed-off-by: Yunpeng Gao <yunpeng.gao@xxxxxxxxx>
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx>
---
drivers/mmc/core/core.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 7dc0c85..385373db 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1761,7 +1761,7 @@ void mmc_init_erase(struct mmc_card *card)
card->erase_shift = ffs(card->ssr.au) - 1;
} else if (card->ext_csd.hc_erase_size) {
card->pref_erase = card->ext_csd.hc_erase_size;
- } else {
+ } else if (card->erase_size) {
sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
if (sz < 128)
card->pref_erase = 512 * 1024 / 512;
@@ -1778,7 +1778,8 @@ void mmc_init_erase(struct mmc_card *card)
if (sz)
card->pref_erase += card->erase_size - sz;
}
- }
+ } else
+ card->pref_erase = 0;
}
static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
