Messages in this thread | | | Date | Mon, 24 Apr 2017 12:26:38 +0100 | From | Catalin Marinas <> | Subject | Re: [PATCH v3 15/18] arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled |
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On Mon, Apr 24, 2017 at 10:33:29AM +0100, Marc Zyngier wrote: > On 24/04/17 10:14, Hanjun Guo wrote: > > On 2017/4/24 16:40, Marc Zyngier wrote: > >> On 24/04/17 09:25, Lixiaoping (Timmy) wrote: > >>> Sorry about previous email's confidential info. Please forget it. > >>> > >>> +#define ESR_ELx_SYS64_ISS_SYS_CNTFRQ (ESR_ELx_SYS64_ISS_SYS_VAL(3, 3, 14, 0, 0) | \ > >>> + ESR_ELx_SYS64_ISS_DIR_READ) > >>> > >>> I think (3, 3, 14, 0, 0) should be (3, 3, 0, 14, 0)? > >> Thanks for spotting this. I assumed that the sys_reg() and > >> SR_ELx_SYS64_ISS_SYS_VAL() macros took their arguments in the same > >> order. That would have been too easy... ;-) > >> > >> Amended patch below, please let me know if it works for you. > >> > >> Thanks, > >> > >> M. > >> > >> >From 4444c86a97c1a487e12c319fdc197c88631d72b5 Mon Sep 17 00:00:00 2001 > >> From: Marc Zyngier <marc.zyngier@arm.com> > >> Date: Mon, 24 Apr 2017 09:04:03 +0100 > >> Subject: [PATCH] arm64: Add CNTFRQ_EL0 trap handler > >> > >> We now trap accesses to CNTVCT_EL0 when the counter is broken > >> enough to require the kernel to mediate the access. But it > >> turns out that some existing userspace (such as OpenMPI) do > >> probe for the counter frequency, leading to an UNDEF exception > >> as CNTVCT_EL0 and CNTFRQ_EL0 share the same control bit. > >> > >> The fix is to handle the exception the same way we do for CNTVCT_EL0. > >> > >> Fixes: a86bd139f2ae ("arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabled") > >> Reported-by: Hanjun Guo <guohanjun@huawei.com> > >> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> > >> --- > > > > I tested this patch and the undefined instruction error is gone, I can > > get the FREQ in the user space now, thank you very much for the quick > > response. > > > > Tested-by: Hanjun Guo <guohanjun@huawei.com> > > Reviewed-by: Hanjun Guo <guohanjun@huawei.com> > > Thanks for giving it a go. Catalin, can you queue this via the arm64 tree?
Done. Thanks for the quick fix.
-- Catalin
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