| Message ID | 1418209329-28615-1-git-send-email-catalin.marinas@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 12/10/2014 12:02 PM, Catalin Marinas wrote: > Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical > timers when requested) introduces the use of physical counters in the > ARM architected timer driver. However, he arm64 kernel uses CNTVCT in > VDSO. When booting in EL2, the kernel switches to the physical timers to > make things easier for KVM but it continues to use the virtual counter > both in user and kernel. While in such scenario CNTVCT == CNTPCT (since > CNTVOFF is initialised by the kernel to 0), we want to spot firmware > bugs corrupting CNTVOFF early (which would affect CNTVCT). > > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com> > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > --- > > Daniel, > > Do you plan to take this patch and push into mainline (ideally before -rc1)? > Otherwise we can push it via the arm64 tree. I will take care of it. Thanks ! -- Daniel > > Thanks, > > Catalin > > > drivers/clocksource/arm_arch_timer.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c > index 6a79fc4f900c..095c1774592c 100644 > --- a/drivers/clocksource/arm_arch_timer.c > +++ b/drivers/clocksource/arm_arch_timer.c > @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) > > /* Register the CP15 based counter if we have one */ > if (type & ARCH_CP15_TIMER) { > - if (arch_timer_use_virtual) > + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) > arch_timer_read_counter = arch_counter_get_cntvct; > else > arch_timer_read_counter = arch_counter_get_cntpct; >
On Wed, Dec 10, 2014 at 11:04:38AM +0000, Daniel Lezcano wrote: > On 12/10/2014 12:02 PM, Catalin Marinas wrote: > > Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical > > timers when requested) introduces the use of physical counters in the > > ARM architected timer driver. However, he arm64 kernel uses CNTVCT in > > VDSO. When booting in EL2, the kernel switches to the physical timers to > > make things easier for KVM but it continues to use the virtual counter > > both in user and kernel. While in such scenario CNTVCT == CNTPCT (since > > CNTVOFF is initialised by the kernel to 0), we want to spot firmware > > bugs corrupting CNTVOFF early (which would affect CNTVCT). > > > > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > > Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com> > > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > > --- > > > > Daniel, > > > > Do you plan to take this patch and push into mainline (ideally before -rc1)? > > Otherwise we can push it via the arm64 tree. > > I will take care of it. Thanks.
Hi Daniel, On Wed, Dec 10, 2014 at 11:04:38AM +0000, Daniel Lezcano wrote: > On 12/10/2014 12:02 PM, Catalin Marinas wrote: > > Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical > > timers when requested) introduces the use of physical counters in the > > ARM architected timer driver. However, he arm64 kernel uses CNTVCT in > > VDSO. When booting in EL2, the kernel switches to the physical timers to > > make things easier for KVM but it continues to use the virtual counter > > both in user and kernel. While in such scenario CNTVCT == CNTPCT (since > > CNTVOFF is initialised by the kernel to 0), we want to spot firmware > > bugs corrupting CNTVOFF early (which would affect CNTVCT). > > > > Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> > > Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com> > > Cc: Daniel Lezcano <daniel.lezcano@linaro.org> > > --- > > > > Daniel, > > > > Do you plan to take this patch and push into mainline (ideally before -rc1)? > > Otherwise we can push it via the arm64 tree. > > I will take care of it. > > Thanks ! > > -- Daniel What's the state of this patch? It doesn't seem to be in linux-next (next-20141215), which is failing to boot for me due to hitting the BUG in the arm64 arch_counter_get_cntpct. Thanks, Mark. > > > > > Thanks, > > > > Catalin > > > > > > drivers/clocksource/arm_arch_timer.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c > > index 6a79fc4f900c..095c1774592c 100644 > > --- a/drivers/clocksource/arm_arch_timer.c > > +++ b/drivers/clocksource/arm_arch_timer.c > > @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) > > > > /* Register the CP15 based counter if we have one */ > > if (type & ARCH_CP15_TIMER) { > > - if (arch_timer_use_virtual) > > + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) > > arch_timer_read_counter = arch_counter_get_cntvct; > > else > > arch_timer_read_counter = arch_counter_get_cntpct; > > > > > -- > <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs > > Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | > <http://twitter.com/#!/linaroorg> Twitter | > <http://www.linaro.org/linaro-blog/> Blog > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Hi Olof, Arnd, Do you mind to apply this patch ? I was about to take care of it but it depends on the commit: https://git.kernel.org/cgit/linux/kernel/git/arm/arm-soc.git/commit/drivers/clocksource?h=for-next&id=0b46b8a718c6e90910a1b1b0fe797be3c167e186 Thanks -- Daniel On 12/15/2014 11:58 AM, Mark Rutland wrote: > Hi Daniel, > > On Wed, Dec 10, 2014 at 11:04:38AM +0000, Daniel Lezcano wrote: >> On 12/10/2014 12:02 PM, Catalin Marinas wrote: >>> Commit 0b46b8a718c6 (clocksource: arch_timer: Fix code to use physical >>> timers when requested) introduces the use of physical counters in the >>> ARM architected timer driver. However, he arm64 kernel uses CNTVCT in >>> VDSO. When booting in EL2, the kernel switches to the physical timers to >>> make things easier for KVM but it continues to use the virtual counter >>> both in user and kernel. While in such scenario CNTVCT == CNTPCT (since >>> CNTVOFF is initialised by the kernel to 0), we want to spot firmware >>> bugs corrupting CNTVOFF early (which would affect CNTVCT). >>> >>> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> >>> Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com> >>> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> >>> --- >>> >>> Daniel, >>> >>> Do you plan to take this patch and push into mainline (ideally before -rc1)? >>> Otherwise we can push it via the arm64 tree. >> >> I will take care of it. >> >> Thanks ! >> >> -- Daniel > > What's the state of this patch? > > It doesn't seem to be in linux-next (next-20141215), which is failing to > boot for me due to hitting the BUG in the arm64 arch_counter_get_cntpct. > > Thanks, > Mark. > >> >>> >>> Thanks, >>> >>> Catalin >>> >>> >>> drivers/clocksource/arm_arch_timer.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c >>> index 6a79fc4f900c..095c1774592c 100644 >>> --- a/drivers/clocksource/arm_arch_timer.c >>> +++ b/drivers/clocksource/arm_arch_timer.c >>> @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) >>> >>> /* Register the CP15 based counter if we have one */ >>> if (type & ARCH_CP15_TIMER) { >>> - if (arch_timer_use_virtual) >>> + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) >>> arch_timer_read_counter = arch_counter_get_cntvct; >>> else >>> arch_timer_read_counter = arch_counter_get_cntpct; >>> >> >> >> -- >> <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs >> >> Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook | >> <http://twitter.com/#!/linaroorg> Twitter | >> <http://www.linaro.org/linaro-blog/> Blog >> >> >> _______________________________________________ >> linux-arm-kernel mailing list >> linux-arm-kernel@lists.infradead.org >> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 6a79fc4f900c..095c1774592c 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -462,7 +462,7 @@ static void __init arch_counter_register(unsigned type) /* Register the CP15 based counter if we have one */ if (type & ARCH_CP15_TIMER) { - if (arch_timer_use_virtual) + if (IS_ENABLED(CONFIG_ARM64) || arch_timer_use_virtual) arch_timer_read_counter = arch_counter_get_cntvct; else arch_timer_read_counter = arch_counter_get_cntpct;