Commit 8e4e86af authored by David Hildenbrand's avatar David Hildenbrand Committed by Cornelia Huck
Browse files

s390x: remove duplicate definitions of DIAG 501 



When restoring the previously saved instruction in
kvm_arch_remove_sw_breakpoint(), we only restored one byte. Let's use
the sizeof() operator to make sure we restore the entire instruction.

While we are at it, let's remove the duplicate definitions of DIAG 501
and replace its size (used when reading/writing the instruction) with
a sizeof() operator to make the code self explaining and less error-prone.

Signed-off-by: default avatarDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarJens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent 76eb98d5

target-s390x/kvm.c

+12 −8
Original line number Diff line number Diff line
@@ -320,12 +320,16 @@ static void *legacy_s390_alloc(size_t size) 
    return mem == MAP_FAILED ? NULL : mem;

}



/* DIAG 501 is used for sw breakpoints */

static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};



int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)

{

    static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};



    if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 4, 0) ||

        cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)diag_501, 4, 1)) {

    if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,

                            sizeof(diag_501), 0) ||

        cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)diag_501,

                            sizeof(diag_501), 1)) {

        return -EINVAL;

    }

    return 0;
@@ -333,14 +337,14 @@ int kvm_arch_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp) 


int kvm_arch_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)

{

    uint8_t t[4];

    static const uint8_t diag_501[] = {0x83, 0x24, 0x05, 0x01};

    uint8_t t[sizeof(diag_501)];



    if (cpu_memory_rw_debug(cs, bp->pc, t, 4, 0)) {

    if (cpu_memory_rw_debug(cs, bp->pc, t, sizeof(diag_501), 0)) {

        return -EINVAL;

    } else if (memcmp(t, diag_501, 4)) {

    } else if (memcmp(t, diag_501, sizeof(diag_501))) {

        return -EINVAL;

    } else if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn, 1, 1)) {

    } else if (cpu_memory_rw_debug(cs, bp->pc, (uint8_t *)&bp->saved_insn,

                                   sizeof(diag_501), 1)) {

        return -EINVAL;

    }