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KVM: s390: Fix SORTL and DFLTCC instruction format error in __insn32_query

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The __insn32_query() function incorrectly uses the RRF instruction format
for both the SORTL (RRE format) and DFLTCC (RRF format) instructions.
To fix this issue, add separate query functions for SORTL and DFLTCC that
use the appropriate instruction formats.

Additionally pass the query operand as a pointer to the entire array
of 32 elements to slightly optimize performance and readability.

Fixes: d668139718 ("KVM: s390: provide query function for instructions returning 32 byte")
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Signed-off-by: Hariharan Mari <hari55@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
This commit is contained in:
Hariharan Mari 2024-07-04 13:14:00 +02:00 committed by Janosch Frank
parent 47ac09b91b
commit 09c38ad044
1 changed files with 18 additions and 9 deletions
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27
arch/s390/kvm/kvm-s390.c
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@ -348,20 +348,29 @@ static inline int plo_test_bit(unsigned char nr)
return cc == 0;
}
static __always_inline void __insn32_query(unsigned int opcode, u8 *query)
static __always_inline void __sortl_query(u8 (*query)[32])
{
asm volatile(
" lghi 0,0\n"
" lgr 1,%[query]\n"
" la 1,%[query]\n"
/* Parameter registers are ignored */
" .insn rrf,%[opc] << 16,2,4,6,0\n"
" .insn rre,0xb9380000,2,4\n"
: [query] "=R" (*query)
:
: [query] "d" ((unsigned long)query), [opc] "i" (opcode)
: "cc", "memory", "0", "1");
: "cc", "0", "1");
}
#define INSN_SORTL 0xb938
#define INSN_DFLTCC 0xb939
static __always_inline void __dfltcc_query(u8 (*query)[32])
{
asm volatile(
" lghi 0,0\n"
" la 1,%[query]\n"
/* Parameter registers are ignored */
" .insn rrf,0xb9390000,2,4,6,0\n"
: [query] "=R" (*query)
:
: "cc", "0", "1");
}
static void __init kvm_s390_cpu_feat_init(void)
{
@ -415,10 +424,10 @@ static void __init kvm_s390_cpu_feat_init(void)
kvm_s390_available_subfunc.kdsa);
if (test_facility(150)) /* SORTL */
__insn32_query(INSN_SORTL, kvm_s390_available_subfunc.sortl);
__sortl_query(&kvm_s390_available_subfunc.sortl);
if (test_facility(151)) /* DFLTCC */
__insn32_query(INSN_DFLTCC, kvm_s390_available_subfunc.dfltcc);
__dfltcc_query(&kvm_s390_available_subfunc.dfltcc);
if (MACHINE_HAS_ESOP)
allow_cpu_feat(KVM_S390_VM_CPU_FEAT_ESOP);