From: Srivatsa S. Bhat Date: Mon, 28 Apr 2014 18:54:58 +0000 (+0530) Subject: cpufreq: powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end X-Git-Tag: v3.15-rc4~7^2~2^2~1 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=8997b185119966c62c6e95e7b010b4060407e358;p=linux-block.git cpufreq: powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end During frequency transitions, the cpufreq core takes the responsibility of invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end() for those cpufreq drivers that define the ->target_index callback but don't set the ASYNC_NOTIFICATION flag. The powernow-k7 cpufreq driver falls under this category, but this driver was invoking the _begin() and _end() APIs itself around frequency transitions, which led to double invocation of the _begin() API. The _begin API makes contending callers wait until the previous invocation is complete. Hence, the powernow-k7 driver ended up waiting on itself, leading to system hangs during boot. Fix this by removing the calls to the _begin() and _end() APIs from the powernow-k7 driver, since they rightly belong to the cpufreq core. Fixes: 12478cf0c55e (cpufreq: Make sure frequency transitions are serialized) Signed-off-by: Srivatsa S. Bhat Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/cpufreq/powernow-k7.c b/drivers/cpufreq/powernow-k7.c index f911645c3f6d..e61e224475ad 100644 --- a/drivers/cpufreq/powernow-k7.c +++ b/drivers/cpufreq/powernow-k7.c @@ -269,8 +269,6 @@ static int powernow_target(struct cpufreq_policy *policy, unsigned int index) freqs.new = powernow_table[index].frequency; - cpufreq_freq_transition_begin(policy, &freqs); - /* Now do the magic poking into the MSRs. */ if (have_a0 == 1) /* A0 errata 5 */ @@ -290,8 +288,6 @@ static int powernow_target(struct cpufreq_policy *policy, unsigned int index) if (have_a0 == 1) local_irq_enable(); - cpufreq_freq_transition_end(policy, &freqs, 0); - return 0; }