From: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
To: mpe@ellerman.id.au
Cc: benh@kernel.crashing.org, anton@samba.org, paulus@samba.org,
npiggin@gmail.com, linuxppc-dev@lists.ozlabs.org,
Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Subject: [PATCH v10 01/17] powerpc/64: do not trace irqs-off at interrupt return to soft-disabled context
Date: Wed, 20 Dec 2017 09:25:41 +0530 [thread overview]
Message-ID: <1513742157-28768-2-git-send-email-maddy@linux.vnet.ibm.com> (raw)
In-Reply-To: <1513742157-28768-1-git-send-email-maddy@linux.vnet.ibm.com>
From: Nicholas Piggin <npiggin@gmail.com>
When an interrupt is returning to a soft-disabled context (which can
happen for non-maskable interrupts or synchronous interrupts), it goes
through the motions of soft-disabling again, including calling
TRACE_DISABLE_INTS (i.e., trace_hardirqs_off()).
This is not necessary, because we must already be soft-disabled in the
interrupt context, it also may be causing crashes in the irq tracing
code to re-enter as an nmi. Replace it with a warning to ensure that
soft-interrupts are still disabled.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
---
arch/powerpc/kernel/entry_64.S | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 3320bcac7192..b3055ebf20d1 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -911,9 +911,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
beq 1f
rlwinm r7,r7,0,~PACA_IRQ_HARD_DIS
stb r7,PACAIRQHAPPENED(r13)
-1: li r0,0
- stb r0,PACASOFTIRQEN(r13);
- TRACE_DISABLE_INTS
+1:
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_BUG)
+ /* The interrupt should not have soft enabled. */
+ lbz r7,PACASOFTIRQEN(r13)
+ tdnei r7,0
+ EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,BUGFLAG_WARNING
+#endif
b .Ldo_restore
/*
--
2.7.4
next prev parent reply other threads:[~2017-12-20 3:56 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-20 3:55 [PATCH v10 00/17] powerpc: "paca->soft_enabled" based local atomic operation implementation Madhavan Srinivasan
2017-12-20 3:55 ` Madhavan Srinivasan [this message]
2017-12-20 3:55 ` [PATCH v10 02/17] powerpc/64: Add #defines for paca->soft_enabled flags Madhavan Srinivasan
2018-01-22 3:34 ` [v10, " Michael Ellerman
2017-12-20 3:55 ` [PATCH v10 03/17] powerpc/64: Improve inline asm in arch_local_irq_disable Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 04/17] powerpc/64: Fix arch_local_irq_disable() prototype Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 05/17] powerpc/64: move set_soft_enabled(), rename it, add memory clobber Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 06/17] powerpc/64: Implement and use soft_enabled_return API Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 07/17] powerpc/64: Implement and use soft_enabled_set_return API Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 08/17] powerpc/64: Cleanup hard_irq_disable() macro Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 09/17] powerpc/64: Change soft_enabled from flag to bitmask Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 10/17] powerpc/64: Rename soft_enabled to irq_soft_mask Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 11/17] powerpc/64s: Avoid using EXCEPTION_PROLOG_1 macro in MASKABLE_* Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 12/17] powerpc/64s: Add support to take additional parameter in MASKABLE_* macro Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 13/17] powerpc/64s: Add support to mask perf interrupts and replay them Madhavan Srinivasan
2018-01-15 13:23 ` Nicholas Piggin
2017-12-20 3:55 ` [PATCH v10 14/17] powerpc: Add new kconfig IRQ_DEBUG_SUPPORT Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 15/17] powerpc/64s: Add new set of irq_soft_mask_ functions for PMI masking Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 16/17] powerpc: use generic atomic implementation for local_t Madhavan Srinivasan
2017-12-20 3:55 ` [PATCH v10 17/17] powerpc/64s: Implement local_t using irq soft masking Madhavan Srinivasan
2017-12-20 5:02 ` [PATCH v10 00/17] powerpc: "paca->soft_enabled" based local atomic operation implementation Nicholas Piggin
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