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[5.8,098/148] s390/runtime_instrumentation: fix storage key handling

Message ID 20200824082418.734685366@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH Aug. 24, 2020, 8:29 a.m. UTC 
From: Heiko Carstens <hca@linux.ibm.com>

[ Upstream commit 9eaba29c7985236e16468f4e6a49cc18cf01443e ]

The key member of the runtime instrumentation control block contains
only the access key, not the complete storage key. Therefore the value
must be shifted by four bits.
Note: this is only relevant for debugging purposes in case somebody
compiles a kernel with a default storage access key set to a value not
equal to zero.

Fixes: e4b8b3f33fca ("s390: add support for runtime instrumentation")
Reported-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/s390/kernel/runtime_instr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/s390/kernel/runtime_instr.c b/arch/s390/kernel/runtime_instr.c
index 125c7f6e87150..1788a5454b6fc 100644
--- a/arch/s390/kernel/runtime_instr.c
+++ b/arch/s390/kernel/runtime_instr.c
@@ -57,7 +57,7 @@  static void init_runtime_instr_cb(struct runtime_instr_cb *cb)
 	cb->k = 1;
 	cb->ps = 1;
 	cb->pc = 1;
-	cb->key = PAGE_DEFAULT_KEY;
+	cb->key = PAGE_DEFAULT_KEY >> 4;
 	cb->v = 1;
 }