commit: 26fc8775b51484d8c0a671198639c6d5ae60533e From: Guennadi Liakhovetski <[email protected]> Date: Fri, 15 Apr 2011 20:08:19 +0200 Subject: [PATCH] mmc: fix a race between card-detect rescan and clock-gate work instances
Currently there is a race in the MMC core between a card-detect rescan work and the clock-gating work, scheduled from a command completion. Fix it by removing the dedicated clock-gating mutex and using the MMC standard locking mechanism instead. Signed-off-by: Guennadi Liakhovetski <[email protected]> Cc: Simon Horman <[email protected]> Cc: Magnus Damm <[email protected]> Acked-by: Linus Walleij <[email protected]> Cc: <[email protected]> Signed-off-by: Chris Ball <[email protected]> --- drivers/mmc/core/host.c | 9 ++++----- include/linux/mmc/host.h | 1 - 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 461e6a1..2b200c1 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -94,7 +94,7 @@ static void mmc_host_clk_gate_delayed(struct mmc_host *host) spin_unlock_irqrestore(&host->clk_lock, flags); return; } - mutex_lock(&host->clk_gate_mutex); + mmc_claim_host(host); spin_lock_irqsave(&host->clk_lock, flags); if (!host->clk_requests) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -104,7 +104,7 @@ static void mmc_host_clk_gate_delayed(struct mmc_host *host) pr_debug("%s: gated MCI clock\n", mmc_hostname(host)); } spin_unlock_irqrestore(&host->clk_lock, flags); - mutex_unlock(&host->clk_gate_mutex); + mmc_release_host(host); } /* @@ -130,7 +130,7 @@ void mmc_host_clk_ungate(struct mmc_host *host) { unsigned long flags; - mutex_lock(&host->clk_gate_mutex); + mmc_claim_host(host); spin_lock_irqsave(&host->clk_lock, flags); if (host->clk_gated) { spin_unlock_irqrestore(&host->clk_lock, flags); @@ -140,7 +140,7 @@ void mmc_host_clk_ungate(struct mmc_host *host) } host->clk_requests++; spin_unlock_irqrestore(&host->clk_lock, flags); - mutex_unlock(&host->clk_gate_mutex); + mmc_release_host(host); } /** @@ -215,7 +215,6 @@ static inline void mmc_host_clk_init(struct mmc_host *host) host->clk_gated = false; INIT_WORK(&host->clk_gate_work, mmc_host_clk_gate_work); spin_lock_init(&host->clk_lock); - mutex_init(&host->clk_gate_mutex); } /** diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index bcb793e..eb792cb 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -183,7 +183,6 @@ struct mmc_host { struct work_struct clk_gate_work; /* delayed clock gate */ unsigned int clk_old; /* old clock value cache */ spinlock_t clk_lock; /* lock for clk fields */ - struct mutex clk_gate_mutex; /* mutex for clock gating */ #endif /* host specific block data */ _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
