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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org D Scott Phillips writes: > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c > index aacf2f5559a8..b37ff23e625e 100644 > --- a/arch/arm64/kernel/process.c > +++ b/arch/arm64/kernel/process.c > @@ -439,34 +439,23 @@ static void entry_task_switch(struct task_struct *next) > > /* > * ARM erratum 1418040 handling, affecting the 32bit view of CNTVCT. > - * Assuming the virtual counter is enabled at the beginning of times: > - * > - * - disable access when switching from a 64bit task to a 32bit task > - * - enable access when switching from a 32bit task to a 64bit task > + * Ensure access is disabled when switching to a 32bit task, ensure > + * access is enabled when switching to a 64bit task. > */ > -static void erratum_1418040_thread_switch(struct task_struct *prev, > - struct task_struct *next) > +static void erratum_1418040_thread_switch(struct task_struct *next) > { > - bool prev32, next32; > - u64 val; > - > - if (!IS_ENABLED(CONFIG_ARM64_ERRATUM_1418040)) > - return; > + preempt_disable(); > > - prev32 = is_compat_thread(task_thread_info(prev)); > - next32 = is_compat_thread(task_thread_info(next)); > - > - if (prev32 == next32 || !this_cpu_has_cap(ARM64_WORKAROUND_1418040)) > + if (!IS_ENABLED(CONFIG_ARM64_ERRATUM_1418040) || > + !this_cpu_has_cap(ARM64_WORKAROUND_1418040)) > return; Oops, missing preempt_enable() here. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel