From: Arnd Bergmann <arnd@arndb.de> To: Yegor Yefremov <yegorslists@googlemail.com> Cc: Arnd Bergmann <arnd@arndb.de>, Tony Lindgren <tony@atomide.com>, Ard Biesheuvel <ardb@kernel.org>, Linux-OMAP <linux-omap@vger.kernel.org>, linux-clk <linux-clk@vger.kernel.org>, Stephen Boyd <sboyd@kernel.org>, Linux ARM <linux-arm-kernel@lists.infradead.org> Subject: Re: am335x: 5.18.x: system stalling Date: Fri, 27 May 2022 14:53:50 +0200 [thread overview] Message-ID: <CAK8P3a22hmSnS4X93ETLpF7vPtK_F1TD51SK5VvhEz9L9H4i3g@mail.gmail.com> (raw) In-Reply-To: <CAGm1_kvdhqrptEYy8WMfqZqG6gaWoBtAojSW5uXYnyXMVfV=Fw@mail.gmail.com> On Fri, May 27, 2022 at 11:50 AM Yegor Yefremov <yegorslists@googlemail.com> wrote: > > # zcat /proc/config.gz | grep 'CONFIG_ARCH_MULTI_V6\|CONFIG_SMP' > # CONFIG_ARCH_MULTI_V6 is not set > CONFIG_ARCH_MULTI_V6_V7=y > CONFIG_SMP=y > CONFIG_SMP_ON_UP=y > > No stalls. > > # zcat /proc/config.gz | grep 'CONFIG_ARCH_MULTI_V6\|CONFIG_SMP\|ARCH_OMAP2' > CONFIG_ARCH_MULTI_V6=y > CONFIG_ARCH_MULTI_V6_V7=y > CONFIG_ARCH_OMAP2=y > CONFIG_ARCH_OMAP2PLUS=y > CONFIG_ARCH_OMAP2PLUS_TYPICAL=y > > No stalls. > > As soon as I enable both SMP and OMAP2 options the system stalls. Ok, that points to the SMP patching for percpu data, which doesn't happen before the patch, and which is different between loadable modules and the normal code. Can you try out this patch to short-circuit the logic and always return the offset for CPU 0? This is obviously broken on SMP machines but would get around the bit of code that is V6+SMP specific. Arnd diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h index 7545c87c251f..3057c5fef970 100644 --- a/arch/arm/include/asm/percpu.h +++ b/arch/arm/include/asm/percpu.h @@ -25,10 +25,13 @@ static inline void set_my_cpu_offset(unsigned long off) asm volatile("mcr p15, 0, %0, c13, c0, 4" : : "r" (off) : "memory"); } +extern unsigned long __per_cpu_offset[]; static __always_inline unsigned long __my_cpu_offset(void) { unsigned long off; + return __per_cpu_offset[0]; + /* * Read TPIDRPRW. * We want to allow caching the value, so avoid using volatile and
WARNING: multiple messages have this Message-ID (diff)
From: Arnd Bergmann <arnd@arndb.de> To: Yegor Yefremov <yegorslists@googlemail.com> Cc: Arnd Bergmann <arnd@arndb.de>, Tony Lindgren <tony@atomide.com>, Ard Biesheuvel <ardb@kernel.org>, Linux-OMAP <linux-omap@vger.kernel.org>, linux-clk <linux-clk@vger.kernel.org>, Stephen Boyd <sboyd@kernel.org>, Linux ARM <linux-arm-kernel@lists.infradead.org> Subject: Re: am335x: 5.18.x: system stalling Date: Fri, 27 May 2022 14:53:50 +0200 [thread overview] Message-ID: <CAK8P3a22hmSnS4X93ETLpF7vPtK_F1TD51SK5VvhEz9L9H4i3g@mail.gmail.com> (raw) In-Reply-To: <CAGm1_kvdhqrptEYy8WMfqZqG6gaWoBtAojSW5uXYnyXMVfV=Fw@mail.gmail.com> On Fri, May 27, 2022 at 11:50 AM Yegor Yefremov <yegorslists@googlemail.com> wrote: > > # zcat /proc/config.gz | grep 'CONFIG_ARCH_MULTI_V6\|CONFIG_SMP' > # CONFIG_ARCH_MULTI_V6 is not set > CONFIG_ARCH_MULTI_V6_V7=y > CONFIG_SMP=y > CONFIG_SMP_ON_UP=y > > No stalls. > > # zcat /proc/config.gz | grep 'CONFIG_ARCH_MULTI_V6\|CONFIG_SMP\|ARCH_OMAP2' > CONFIG_ARCH_MULTI_V6=y > CONFIG_ARCH_MULTI_V6_V7=y > CONFIG_ARCH_OMAP2=y > CONFIG_ARCH_OMAP2PLUS=y > CONFIG_ARCH_OMAP2PLUS_TYPICAL=y > > No stalls. > > As soon as I enable both SMP and OMAP2 options the system stalls. Ok, that points to the SMP patching for percpu data, which doesn't happen before the patch, and which is different between loadable modules and the normal code. Can you try out this patch to short-circuit the logic and always return the offset for CPU 0? This is obviously broken on SMP machines but would get around the bit of code that is V6+SMP specific. Arnd diff --git a/arch/arm/include/asm/percpu.h b/arch/arm/include/asm/percpu.h index 7545c87c251f..3057c5fef970 100644 --- a/arch/arm/include/asm/percpu.h +++ b/arch/arm/include/asm/percpu.h @@ -25,10 +25,13 @@ static inline void set_my_cpu_offset(unsigned long off) asm volatile("mcr p15, 0, %0, c13, c0, 4" : : "r" (off) : "memory"); } +extern unsigned long __per_cpu_offset[]; static __always_inline unsigned long __my_cpu_offset(void) { unsigned long off; + return __per_cpu_offset[0]; + /* * Read TPIDRPRW. * We want to allow caching the value, so avoid using volatile and _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2022-05-27 12:54 UTC|newest] Thread overview: 115+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-05-04 10:35 am335x: 5.18.x: system stalling Yegor Yefremov 2022-05-05 5:08 ` Tony Lindgren 2022-05-11 14:16 ` Yegor Yefremov 2022-05-12 5:41 ` Tony Lindgren 2022-05-12 5:41 ` Tony Lindgren 2022-05-12 8:14 ` Arnd Bergmann 2022-05-12 8:14 ` Arnd Bergmann 2022-05-12 8:42 ` Arnd Bergmann 2022-05-12 8:42 ` Arnd Bergmann 2022-05-12 10:20 ` Yegor Yefremov 2022-05-12 10:20 ` Yegor Yefremov 2022-05-19 16:52 ` Yegor Yefremov 2022-05-19 16:52 ` Yegor Yefremov 2022-05-21 19:41 ` Arnd Bergmann 2022-05-21 19:41 ` Arnd Bergmann 2022-05-24 13:38 ` Yegor Yefremov 2022-05-24 13:38 ` Yegor Yefremov 2022-05-24 14:19 ` Tony Lindgren 2022-05-24 14:19 ` Tony Lindgren 2022-05-26 5:49 ` Yegor Yefremov 2022-05-26 5:49 ` Yegor Yefremov 2022-05-26 6:20 ` Tony Lindgren 2022-05-26 6:20 ` Tony Lindgren 2022-05-26 8:19 ` Ard Biesheuvel 2022-05-26 8:19 ` Ard Biesheuvel 2022-05-26 12:37 ` Yegor Yefremov 2022-05-26 12:37 ` Yegor Yefremov 2022-05-26 14:15 ` Arnd Bergmann 2022-05-26 14:15 ` Arnd Bergmann 2022-05-27 4:44 ` Yegor Yefremov 2022-05-27 4:44 ` Yegor Yefremov 2022-05-27 6:38 ` Arnd Bergmann 2022-05-27 6:38 ` Arnd Bergmann 2022-05-27 6:50 ` Tony Lindgren 2022-05-27 6:50 ` Tony Lindgren 2022-05-27 6:57 ` Arnd Bergmann 2022-05-27 6:57 ` Arnd Bergmann 2022-05-27 8:17 ` Yegor Yefremov 2022-05-27 8:17 ` Yegor Yefremov 2022-05-27 8:38 ` Arnd Bergmann 2022-05-27 8:38 ` Arnd Bergmann 2022-05-27 9:50 ` Yegor Yefremov 2022-05-27 9:50 ` Yegor Yefremov 2022-05-27 12:53 ` Arnd Bergmann [this message] 2022-05-27 12:53 ` Arnd Bergmann 2022-05-27 13:12 ` Ard Biesheuvel 2022-05-27 13:12 ` Ard Biesheuvel 2022-05-27 14:12 ` Arnd Bergmann 2022-05-27 14:12 ` Arnd Bergmann 2022-05-28 5:48 ` Yegor Yefremov 2022-05-28 5:48 ` Yegor Yefremov 2022-05-28 7:53 ` Arnd Bergmann 2022-05-28 7:53 ` Arnd Bergmann 2022-05-28 8:29 ` Yegor Yefremov 2022-05-28 8:29 ` Yegor Yefremov 2022-05-28 9:07 ` Ard Biesheuvel 2022-05-28 9:07 ` Ard Biesheuvel 2022-05-28 13:01 ` Yegor Yefremov 2022-05-28 13:01 ` Yegor Yefremov 2022-05-28 13:13 ` Arnd Bergmann 2022-05-28 13:13 ` Arnd Bergmann 2022-05-28 19:28 ` Yegor Yefremov 2022-05-28 19:28 ` Yegor Yefremov 2022-05-30 10:16 ` Ard Biesheuvel 2022-05-30 10:16 ` Ard Biesheuvel 2022-05-30 12:09 ` Yegor Yefremov 2022-05-30 12:09 ` Yegor Yefremov 2022-05-30 13:54 ` Arnd Bergmann 2022-05-30 13:54 ` Arnd Bergmann 2022-05-30 15:14 ` Ard Biesheuvel 2022-05-30 15:14 ` Ard Biesheuvel 2022-05-31 8:36 ` Yegor Yefremov 2022-05-31 8:36 ` Yegor Yefremov 2022-05-31 14:16 ` Yegor Yefremov 2022-05-31 14:16 ` Yegor Yefremov 2022-05-31 15:22 ` Arnd Bergmann 2022-05-31 15:22 ` Arnd Bergmann 2022-06-01 7:36 ` Yegor Yefremov 2022-06-01 7:36 ` Yegor Yefremov 2022-06-01 7:59 ` Arnd Bergmann 2022-06-01 7:59 ` Arnd Bergmann 2022-06-01 8:08 ` Ard Biesheuvel 2022-06-01 8:08 ` Ard Biesheuvel 2022-06-01 9:27 ` Ard Biesheuvel 2022-06-01 9:27 ` Ard Biesheuvel 2022-06-01 10:03 ` Yegor Yefremov 2022-06-01 10:03 ` Yegor Yefremov 2022-06-01 10:06 ` Ard Biesheuvel 2022-06-01 10:06 ` Ard Biesheuvel 2022-06-01 10:46 ` Yegor Yefremov 2022-06-01 10:46 ` Yegor Yefremov 2022-06-01 10:49 ` Ard Biesheuvel 2022-06-01 10:49 ` Ard Biesheuvel 2022-06-02 10:17 ` Yegor Yefremov 2022-06-02 10:17 ` Yegor Yefremov 2022-06-02 10:37 ` Ard Biesheuvel 2022-06-02 10:37 ` Ard Biesheuvel 2022-06-02 12:27 ` Yegor Yefremov 2022-06-02 12:27 ` Yegor Yefremov 2022-06-03 8:54 ` Yegor Yefremov 2022-06-03 8:54 ` Yegor Yefremov 2022-06-03 9:32 ` Arnd Bergmann 2022-06-03 9:32 ` Arnd Bergmann 2022-06-03 19:11 ` Yegor Yefremov 2022-06-03 19:11 ` Yegor Yefremov 2022-06-03 20:46 ` Arnd Bergmann 2022-06-03 20:46 ` Arnd Bergmann 2022-06-05 14:59 ` Ard Biesheuvel 2022-06-05 14:59 ` Ard Biesheuvel 2022-06-07 8:55 ` Yegor Yefremov 2022-06-07 8:55 ` Yegor Yefremov 2022-08-12 7:35 ` Arnd Bergmann 2022-08-12 7:35 ` Arnd Bergmann 2022-05-24 14:36 ` Arnd Bergmann 2022-05-24 14:36 ` Arnd Bergmann
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