From: Heiko Carstens heiko.carstens@de.ibm.com
commit b1c41ac3ce569b04644bb1e3fd28926604637da3 upstream.
The inline assembly constraints of __insn32_query() tell the compiler that only the first byte of "query" is being written to. Intended was probably that 32 bytes are written to.
Fix and simplify the code and just use a "memory" clobber.
Fixes: d668139718a9 ("KVM: s390: provide query function for instructions returning 32 byte") Cc: stable@vger.kernel.org # v5.2+ Acked-by: Christian Borntraeger borntraeger@de.ibm.com Signed-off-by: Heiko Carstens heiko.carstens@de.ibm.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/s390/kvm/kvm-s390.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -332,7 +332,7 @@ static inline int plo_test_bit(unsigned return cc == 0; }
-static inline void __insn32_query(unsigned int opcode, u8 query[32]) +static inline void __insn32_query(unsigned int opcode, u8 *query) { register unsigned long r0 asm("0") = 0; /* query function */ register unsigned long r1 asm("1") = (unsigned long) query; @@ -340,9 +340,9 @@ static inline void __insn32_query(unsign asm volatile( /* Parameter regs are ignored */ " .insn rrf,%[opc] << 16,2,4,6,0\n" - : "=m" (*query) + : : "d" (r0), "a" (r1), [opc] "i" (opcode) - : "cc"); + : "cc", "memory"); }
#define INSN_SORTL 0xb938