From: Christophe Leroy <christophe.leroy@c-s.fr>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>,
Scott Wood <oss@buserror.net>
Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH] powerpc/8xx: CONFIG_DEBUG_PAGEALLOC requires ITLBmiss for kernel addresses
Date: Wed, 3 Feb 2016 23:34:21 +0100 (CET) [thread overview]
Message-ID: <20160203223426.60C681A2446@localhost.localdomain> (raw)
When CONFIG_DEBUG_PAGEALLOC is activated, the initial TLB mapping gets
flushed to track accesses to wrong areas. Therefore, kernel addresses
will also generate ITLB misses.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
arch/powerpc/kernel/head_8xx.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 78c1eba..e629e28 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -329,7 +329,7 @@ InstructionTLBMiss:
/* If we are faulting a kernel address, we have to use the
* kernel page tables.
*/
-#ifdef CONFIG_MODULES
+#if defined(CONFIG_MODULES) || defined (CONFIG_DEBUG_PAGEALLOC)
/* Only modules will cause ITLB Misses as we always
* pin the first 8MB of kernel memory */
mfspr r11, SPRN_SRR0 /* Get effective address of fault */
--
2.1.0
reply other threads:[~2016-02-03 22:34 UTC|newest]
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