From mboxrd@z Thu Jan 1 00:00:00 1970 From: elder@linaro.org (Alex Elder) Date: Mon, 21 Apr 2014 16:53:06 -0500 Subject: [PATCH v2 05/10] ARM: bcm: don't special-case CPU 0 in bcm_kona_smc() In-Reply-To: <1398117191-2433-1-git-send-email-elder@linaro.org> References: <1398117191-2433-1-git-send-email-elder@linaro.org> Message-ID: <1398117191-2433-6-git-send-email-elder@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org There's logic in bcm_kona_smc() to ensure __bcm_kona_smc() gets called on CPU 0; if already executing on CPU 0, that function is called directly. The direct call is not protected from interrupts, however, which is not safe. Note that smp_call_function_single() is designed to handle the case where the target cpu is the current one. It also gets a reference to the CPU and disables IRQs across the call. So we can simplify things and at the same time be protected against interrupts by calling smp_call_function_single() unconditionally. Signed-off-by: Alex Elder Reviewed-by: Tim Kryger Reviewed-by: Markus Mayer Reviewed-by: Matt Porter --- arch/arm/mach-bcm/bcm_kona_smc.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) diff --git a/arch/arm/mach-bcm/bcm_kona_smc.c b/arch/arm/mach-bcm/bcm_kona_smc.c index 47cf360..6fdcf96 100644 --- a/arch/arm/mach-bcm/bcm_kona_smc.c +++ b/arch/arm/mach-bcm/bcm_kona_smc.c @@ -114,12 +114,7 @@ unsigned bcm_kona_smc(unsigned service_id, unsigned arg0, unsigned arg1, * Due to a limitation of the secure monitor, we must use the SMP * infrastructure to forward all secure monitor calls to Core 0. */ - if (get_cpu() != 0) - smp_call_function_single(0, __bcm_kona_smc, (void *)&data, 1); - else - __bcm_kona_smc(&data); - - put_cpu(); + smp_call_function_single(0, __bcm_kona_smc, &data, 1); return data.result; } -- 1.9.1