This is a note to let you know that I've just added the patch titled
mmc: sdhci: Fix sleep in atomic after inserting SD card
to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mmc-sdhci-fix-sleep-in-atomic-after-inserting-sd-card.patch
and it can be found in the queue-3.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 2836766a9d0bd02c66073f8dd44796e6cc23848d Mon Sep 17 00:00:00 2001
From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Date: Mon, 5 Jan 2015 10:50:15 +0100
Subject: mmc: sdhci: Fix sleep in atomic after inserting SD card
From: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
commit 2836766a9d0bd02c66073f8dd44796e6cc23848d upstream.
Sleep in atomic context happened on Trats2 board after inserting or
removing SD card because mmc_gpio_get_cd() was called under spin lock.
Fix this by moving card detection earlier, before acquiring spin lock.
The mmc_gpio_get_cd() call does not have to be protected by spin lock
because it does not access any sdhci internal data.
The sdhci_do_get_cd() call access host flags (SDHCI_DEVICE_DEAD). After
moving it out side of spin lock it could theoretically race with driver
removal but still there is no actual protection against manual card
eject.
Dmesg after inserting SD card:
[ 41.663414] BUG: sleeping function called from invalid context at drivers/gpio/gpiolib.c:1511
[ 41.670469] in_atomic(): 1, irqs_disabled(): 128, pid: 30, name: kworker/u8:1
[ 41.677580] INFO: lockdep is turned off.
[ 41.681486] irq event stamp: 61972
[ 41.684872] hardirqs last enabled at (61971): [<c0490ee0>] _raw_spin_unlock_irq+0x24/0x5c
[ 41.693118] hardirqs last disabled at (61972): [<c04907ac>] _raw_spin_lock_irq+0x18/0x54
[ 41.701190] softirqs last enabled at (61648): [<c0026fd4>] __do_softirq+0x234/0x2c8
[ 41.708914] softirqs last disabled at (61631): [<c00273a0>] irq_exit+0xd0/0x114
[ 41.716206] Preemption disabled at:[< (null)>] (null)
[ 41.721500]
[ 41.722985] CPU: 3 PID: 30 Comm: kworker/u8:1 Tainted: G W 3.18.0-rc5-next-20141121 #883
[ 41.732111] Workqueue: kmmcd mmc_rescan
[ 41.735945] [<c0014d2c>] (unwind_backtrace) from [<c0011c80>] (show_stack+0x10/0x14)
[ 41.743661] [<c0011c80>] (show_stack) from [<c0489d14>] (dump_stack+0x70/0xbc)
[ 41.750867] [<c0489d14>] (dump_stack) from [<c0228b74>] (gpiod_get_raw_value_cansleep+0x18/0x30)
[ 41.759628] [<c0228b74>] (gpiod_get_raw_value_cansleep) from [<c03646e8>] (mmc_gpio_get_cd+0x38/0x58)
[ 41.768821] [<c03646e8>] (mmc_gpio_get_cd) from [<c036d378>] (sdhci_request+0x50/0x1a4)
[ 41.776808] [<c036d378>] (sdhci_request) from [<c0357934>] (mmc_start_request+0x138/0x268)
[ 41.785051] [<c0357934>] (mmc_start_request) from [<c0357cc8>] (mmc_wait_for_req+0x58/0x1a0)
[ 41.793469] [<c0357cc8>] (mmc_wait_for_req) from [<c0357e68>] (mmc_wait_for_cmd+0x58/0x78)
[ 41.801714] [<c0357e68>] (mmc_wait_for_cmd) from [<c0361c00>] (mmc_io_rw_direct_host+0x98/0x124)
[ 41.810480] [<c0361c00>] (mmc_io_rw_direct_host) from [<c03620f8>] (sdio_reset+0x2c/0x64)
[ 41.818641] [<c03620f8>] (sdio_reset) from [<c035a3d8>] (mmc_rescan+0x254/0x2e4)
[ 41.826028] [<c035a3d8>] (mmc_rescan) from [<c003a0e0>] (process_one_work+0x180/0x3f4)
[ 41.833920] [<c003a0e0>] (process_one_work) from [<c003a3bc>] (worker_thread+0x34/0x4b0)
[ 41.841991] [<c003a3bc>] (worker_thread) from [<c003fed8>] (kthread+0xe4/0x104)
[ 41.849285] [<c003fed8>] (kthread) from [<c000f268>] (ret_from_fork+0x14/0x2c)
[ 42.038276] mmc0: new high speed SDHC card at address 1234
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
Fixes: 94144a465dd0 ("mmc: sdhci: add get_cd() implementation")
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1343,6 +1343,8 @@ static void sdhci_request(struct mmc_hos
sdhci_runtime_pm_get(host);
+ present = mmc_gpio_get_cd(host->mmc);
+
spin_lock_irqsave(&host->lock, flags);
WARN_ON(host->mrq != NULL);
@@ -1371,7 +1373,6 @@ static void sdhci_request(struct mmc_hos
* zero: cd-gpio is used, and card is removed
* one: cd-gpio is used, and card is present
*/
- present = mmc_gpio_get_cd(host->mmc);
if (present < 0) {
/* If polling, assume that the card is always present. */
if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
@@ -2082,15 +2083,18 @@ static void sdhci_card_event(struct mmc_
{
struct sdhci_host *host = mmc_priv(mmc);
unsigned long flags;
+ int present;
/* First check if client has provided their own card event */
if (host->ops->card_event)
host->ops->card_event(host);
+ present = sdhci_do_get_cd(host);
+
spin_lock_irqsave(&host->lock, flags);
/* Check host->mrq first in case we are runtime suspended */
- if (host->mrq && !sdhci_do_get_cd(host)) {
+ if (host->mrq && !present) {
pr_err("%s: Card removed during transfer!\n",
mmc_hostname(host->mmc));
pr_err("%s: Resetting controller.\n",
Patches currently in stable-queue which might be from k.kozlowski@xxxxxxxxxxx are
queue-3.14/mmc-sdhci-fix-sleep-in-atomic-after-inserting-sd-card.patch
--
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