summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLauri Hintsala <lauri.hintsala@bluegiga.com>2012-07-17 16:16:10 +0200
committerChris Ball <cjb@laptop.org>2012-09-04 19:58:06 +0200
commitfc108d24d3a6da63576a460e122fa1df0cbdea20 (patch)
tree2d10611b82d11f7aab6230f9a8b1c6eadb4092b1
parentmmc: mxs-mmc: fix deadlock in SDIO IRQ case (diff)
downloadlinux-fc108d24d3a6da63576a460e122fa1df0cbdea20.tar.xz
linux-fc108d24d3a6da63576a460e122fa1df0cbdea20.zip
mmc: mxs-mmc: fix deadlock caused by recursion loop
Release the lock before mmc_signal_sdio_irq is called by mxs_mmc_enable_sdio_irq. Backtrace: [ 65.470000] ============================================= [ 65.470000] [ INFO: possible recursive locking detected ] [ 65.470000] 3.5.0-rc5 #2 Not tainted [ 65.470000] --------------------------------------------- [ 65.470000] ksdioirqd/mmc0/73 is trying to acquire lock: [ 65.470000] (&(&host->lock)->rlock#2){-.-...}, at: [<bf054120>] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] but task is already holding lock: [ 65.470000] (&(&host->lock)->rlock#2){-.-...}, at: [<bf054120>] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] other info that might help us debug this: [ 65.470000] Possible unsafe locking scenario: [ 65.470000] [ 65.470000] CPU0 [ 65.470000] ---- [ 65.470000] lock(&(&host->lock)->rlock#2); [ 65.470000] lock(&(&host->lock)->rlock#2); [ 65.470000] [ 65.470000] *** DEADLOCK *** [ 65.470000] [ 65.470000] May be due to missing lock nesting notation [ 65.470000] [ 65.470000] 1 lock held by ksdioirqd/mmc0/73: [ 65.470000] #0: (&(&host->lock)->rlock#2){-.-...}, at: [<bf054120>] mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc] [ 65.470000] [ 65.470000] stack backtrace: [ 65.470000] [<c0014990>] (unwind_backtrace+0x0/0xf4) from [<c005ccb8>] (__lock_acquire+0x14f8/0x1b98) [ 65.470000] [<c005ccb8>] (__lock_acquire+0x14f8/0x1b98) from [<c005d3f8>] (lock_acquire+0xa0/0x108) [ 65.470000] [<c005d3f8>] (lock_acquire+0xa0/0x108) from [<c02f671c>] (_raw_spin_lock_irqsave+0x48/0x5c) [ 65.470000] [<c02f671c>] (_raw_spin_lock_irqsave+0x48/0x5c) from [<bf054120>] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) [ 65.470000] [<bf054120>] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) from [<bf0541d0>] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) [ 65.470000] [<bf0541d0>] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) from [<c0219b38>] (sdio_irq_thread+0x1bc/0x274) [ 65.470000] [<c0219b38>] (sdio_irq_thread+0x1bc/0x274) from [<c003c324>] (kthread+0x8c/0x98) [ 65.470000] [<c003c324>] (kthread+0x8c/0x98) from [<c00101ac>] (kernel_thread_exit+0x0/0x8) [ 65.470000] BUG: spinlock lockup suspected on CPU#0, ksdioirqd/mmc0/73 [ 65.470000] lock: 0xc3358724, .magic: dead4ead, .owner: ksdioirqd/mmc0/73, .owner_cpu: 0 [ 65.470000] [<c0014990>] (unwind_backtrace+0x0/0xf4) from [<c01b46b0>] (do_raw_spin_lock+0x100/0x144) [ 65.470000] [<c01b46b0>] (do_raw_spin_lock+0x100/0x144) from [<c02f6724>] (_raw_spin_lock_irqsave+0x50/0x5c) [ 65.470000] [<c02f6724>] (_raw_spin_lock_irqsave+0x50/0x5c) from [<bf054120>] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) [ 65.470000] [<bf054120>] (mxs_mmc_enable_sdio_irq+0x18/0xdc [mxs_mmc]) from [<bf0541d0>] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) [ 65.470000] [<bf0541d0>] (mxs_mmc_enable_sdio_irq+0xc8/0xdc [mxs_mmc]) from [<c0219b38>] (sdio_irq_thread+0x1bc/0x274) [ 65.470000] [<c0219b38>] (sdio_irq_thread+0x1bc/0x274) from [<c003c324>] (kthread+0x8c/0x98) [ 65.470000] [<c003c324>] (kthread+0x8c/0x98) from [<c00101ac>] (kernel_thread_exit+0x0/0x8) Reported-by: Attila Kinali <attila@kinali.ch> Signed-off-by: Lauri Hintsala <lauri.hintsala@bluegiga.com> Acked-by: Shawn Guo <shawn.guo@linaro.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Chris Ball <cjb@laptop.org>
-rw-r--r--drivers/mmc/host/mxs-mmc.c10
1 files changed, 5 insertions, 5 deletions
diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
index e62e58e5053d..ad3fcea1269e 100644
--- a/drivers/mmc/host/mxs-mmc.c
+++ b/drivers/mmc/host/mxs-mmc.c
@@ -644,11 +644,6 @@ static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
host->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
writel(BM_SSP_CTRL1_SDIO_IRQ_EN,
host->base + HW_SSP_CTRL1(host) + STMP_OFFSET_REG_SET);
-
- if (readl(host->base + HW_SSP_STATUS(host)) &
- BM_SSP_STATUS_SDIO_IRQ)
- mmc_signal_sdio_irq(host->mmc);
-
} else {
writel(BM_SSP_CTRL0_SDIO_IRQ_CHECK,
host->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
@@ -657,6 +652,11 @@ static void mxs_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
}
spin_unlock_irqrestore(&host->lock, flags);
+
+ if (enable && readl(host->base + HW_SSP_STATUS(host)) &
+ BM_SSP_STATUS_SDIO_IRQ)
+ mmc_signal_sdio_irq(host->mmc);
+
}
static const struct mmc_host_ops mxs_mmc_ops = {