From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x242.google.com (mail-pf0-x242.google.com [IPv6:2607:f8b0:400e:c00::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40l54z3WCwzF3Dy for ; Tue, 15 May 2018 02:00:19 +1000 (AEST) Received: by mail-pf0-x242.google.com with SMTP id w129-v6so6236384pfd.3 for ; Mon, 14 May 2018 09:00:19 -0700 (PDT) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Cc: Nicholas Piggin Subject: [PATCH 1/2] powerpc/powernv: Fix opal_event_shutdown() called with interrupts disabled Date: Tue, 15 May 2018 01:59:46 +1000 Message-Id: <20180514155947.22753-2-npiggin@gmail.com> In-Reply-To: <20180514155947.22753-1-npiggin@gmail.com> References: <20180514155947.22753-1-npiggin@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , A kernel crash in process context that calls emergency_restart from panic will end up calling opal_event_shutdown with interrupts disabled but not in interrupt. This causes a sleeping function to be called which gives the following warning with sysrq+c: Rebooting in 10 seconds.. BUG: sleeping function called from invalid context at kernel/locking/mutex.c:238 in_atomic(): 0, irqs_disabled(): 1, pid: 7669, name: bash CPU: 20 PID: 7669 Comm: bash Tainted: G D W 4.17.0-rc5+ #3 Call Trace: dump_stack+0xb0/0xf4 (unreliable) ___might_sleep+0x174/0x1a0 mutex_lock+0x38/0xb0 __free_irq+0x68/0x460 free_irq+0x70/0xc0 opal_event_shutdown+0xb4/0xf0 opal_shutdown+0x24/0xa0 pnv_shutdown+0x28/0x40 machine_shutdown+0x44/0x60 machine_restart+0x28/0x80 emergency_restart+0x30/0x50 panic+0x2a0/0x328 oops_end+0x1ec/0x1f0 bad_page_fault+0xe8/0x154 handle_page_fault+0x34/0x38 --- interrupt: 300 at sysrq_handle_crash+0x44/0x60 LR = __handle_sysrq+0xfc/0x260 flag_spec.62335+0x12b844/0x1e8db4 (unreliable) __handle_sysrq+0xfc/0x260 write_sysrq_trigger+0xa8/0xb0 proc_reg_write+0xac/0x110 __vfs_write+0x6c/0x240 vfs_write+0xd0/0x240 ksys_write+0x6c/0x110 Fixes: 9f0fd0499d30 ("powerpc/powernv: Add a virtual irqchip for opal events") Signed-off-by: Nicholas Piggin --- arch/powerpc/platforms/powernv/opal-irqchip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/powernv/opal-irqchip.c b/arch/powerpc/platforms/powernv/opal-irqchip.c index 9d1b8c0aaf93..05ffe05f0fdc 100644 --- a/arch/powerpc/platforms/powernv/opal-irqchip.c +++ b/arch/powerpc/platforms/powernv/opal-irqchip.c @@ -177,7 +177,7 @@ void opal_event_shutdown(void) if (!opal_irqs[i]) continue; - if (in_interrupt()) + if (in_interrupt() || irqs_disabled()) disable_irq_nosync(opal_irqs[i]); else free_irq(opal_irqs[i], NULL); -- 2.17.0