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Subject[PATCH 5.4-rc1 BUILD FIX] s390: mark __cpacf_query() as __always_inline
arch/s390/kvm/kvm-s390.c calls on several places __cpacf_query() directly, 
which makes it impossible to meet the "i" constraint for the asm operands
(opcode in this case).

As we are now force-enabling CONFIG_OPTIMIZE_INLINING on all
architectures, this causes a build failure on s390:

In file included from arch/s390/kvm/kvm-s390.c:44:
./arch/s390/include/asm/cpacf.h: In function '__cpacf_query':
./arch/s390/include/asm/cpacf.h:179:2: warning: asm operand 3 probably doesn't match constraints
179 | asm volatile(
| ^~~
./arch/s390/include/asm/cpacf.h:179:2: error: impossible constraint in 'asm'

Mark __cpacf_query() as __always_inline in order to fix that, analogically
how we fixes __cpacf_check_opcode(), cpacf_query_func() and scpacf_query()

Reported-and-tested-by: Michal Kubecek <>
Fixes: d83623c5eab2 ("s390: mark __cpacf_check_opcode() and cpacf_query_func() as __always_inline")
Fixes: e60fb8bf68d4 ("s390/cpacf: mark scpacf_query() as __always_inline")
Fixes: ac7c3e4ff401 ("compiler: enable CONFIG_OPTIMIZE_INLINING forcibly")
Fixes: 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING")
Signed-off-by: Jiri Kosina <>

I am wondering how is it possible that none of the build-testing
infrastructure we have running against linux-next caught this? Not enough
non-x86 coverage?

arch/s390/include/asm/cpacf.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/include/asm/cpacf.h b/arch/s390/include/asm/cpacf.h
index a092f63aac6a..c0f3bfeddcbe 100644
--- a/arch/s390/include/asm/cpacf.h
+++ b/arch/s390/include/asm/cpacf.h
@@ -171,7 +171,7 @@ typedef struct { unsigned char bytes[16]; } cpacf_mask_t;
* Returns 1 if @func is available for @opcode, 0 otherwise
-static inline void __cpacf_query(unsigned int opcode, cpacf_mask_t *mask)
+static __always_inline void __cpacf_query(unsigned int opcode, cpacf_mask_t *mask)
register unsigned long r0 asm("0") = 0; /* query function */
register unsigned long r1 asm("1") = (unsigned long) mask;
Jiri Kosina

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