diff mbox series

[V2] powerpc/pseries/svm: Remove unwanted check for shared_lppaca_size

Message ID 20200619070113.16696-1-sathnaga@linux.vnet.ibm.com (mailing list archive)
State Accepted
Commit b710d27bf72068b15b2f0305d825988183e2ff28
Headers show
Series [V2] powerpc/pseries/svm: Remove unwanted check for shared_lppaca_size | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch success Successfully applied on branch powerpc/merge (c3405d517d606e965030026daec198d314f20195)
snowpatch_ozlabs/build-ppc64le success Build succeeded
snowpatch_ozlabs/build-ppc64be success Build succeeded
snowpatch_ozlabs/build-ppc64e success Build succeeded
snowpatch_ozlabs/build-pmac32 success Build succeeded
snowpatch_ozlabs/checkpatch warning total: 0 errors, 1 warnings, 0 checks, 8 lines checked
snowpatch_ozlabs/needsstable warning Please consider tagging this patch for stable!

Commit Message

Satheesh Rajendran June 19, 2020, 7:01 a.m. UTC
Early secure guest boot hits the below crash while booting with
vcpus numbers aligned with page boundary for PAGE size of 64k
and LPPACA size of 1k i.e 64, 128 etc, due to the BUG_ON assert
for shared_lppaca_total_size equal to shared_lppaca_size,

 [    0.000000] Partition configured for 64 cpus.
 [    0.000000] CPU maps initialized for 1 thread per core
 [    0.000000] ------------[ cut here ]------------
 [    0.000000] kernel BUG at arch/powerpc/kernel/paca.c:89!
 [    0.000000] Oops: Exception in kernel mode, sig: 5 [#1]
 [    0.000000] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries

which is not necessary, let's remove it.

Fixes: bd104e6db6f0 ("powerpc/pseries/svm: Use shared memory for LPPACA structures")
Cc: linux-kernel@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
---

V2:
Added Reviewed by Thiago and Laurent.
Added Fixes tag as per Thiago suggest.

V1: https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20200609105731.14032-1-sathnaga@linux.vnet.ibm.com/ 
---
 arch/powerpc/kernel/paca.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Michael Ellerman July 16, 2020, 12:47 p.m. UTC | #1
On Fri, 19 Jun 2020 12:31:13 +0530, Satheesh Rajendran wrote:
> Early secure guest boot hits the below crash while booting with
> vcpus numbers aligned with page boundary for PAGE size of 64k
> and LPPACA size of 1k i.e 64, 128 etc, due to the BUG_ON assert
> for shared_lppaca_total_size equal to shared_lppaca_size,
> 
>  [    0.000000] Partition configured for 64 cpus.
>  [    0.000000] CPU maps initialized for 1 thread per core
>  [    0.000000] ------------[ cut here ]------------
>  [    0.000000] kernel BUG at arch/powerpc/kernel/paca.c:89!
>  [    0.000000] Oops: Exception in kernel mode, sig: 5 [#1]
>  [    0.000000] LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
> 
> [...]

Applied to powerpc/fixes.

[1/1] powerpc/pseries/svm: Fix incorrect check for shared_lppaca_size
      https://git.kernel.org/powerpc/c/b710d27bf72068b15b2f0305d825988183e2ff28

cheers
diff mbox series

Patch

diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index 2168372b792d..74da65aacbc9 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -87,7 +87,7 @@  static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
 	 * This is very early in boot, so no harm done if the kernel crashes at
 	 * this point.
 	 */
-	BUG_ON(shared_lppaca_size >= shared_lppaca_total_size);
+	BUG_ON(shared_lppaca_size > shared_lppaca_total_size);
 
 	return ptr;
 }