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linux-user/ppc: Fix XER access in save/restore_user_regs

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We should use cpu_read_xer/cpu_write_xer to save/restore the complete
register since some of its bits are in other fields of CPUPPCState. A
test is added to prevent future regressions.

Fixes: da91a00f19 ("target-ppc: Split out SO, OV, CA fields from XER")
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20211014223234.127012-2-matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Matheus Ferst 2021-10-14 19:32:31 -03:00 committed by David Gibson
parent 252fcf36bb
commit 66c6b40aba
4 changed files with 52 additions and 3 deletions
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9
linux-user/ppc/signal.c
View File

@ -242,7 +242,7 @@ static void save_user_regs(CPUPPCState *env, struct target_mcontext *frame)
__put_user(env->nip, &frame->mc_gregs[TARGET_PT_NIP]);
__put_user(env->ctr, &frame->mc_gregs[TARGET_PT_CTR]);
__put_user(env->lr, &frame->mc_gregs[TARGET_PT_LNK]);
__put_user(env->xer, &frame->mc_gregs[TARGET_PT_XER]);
__put_user(cpu_read_xer(env), &frame->mc_gregs[TARGET_PT_XER]);
for (i = 0; i < ARRAY_SIZE(env->crf); i++) {
ccr |= env->crf[i] << (32 - ((i + 1) * 4));
@ -315,6 +315,7 @@ static void restore_user_regs(CPUPPCState *env,
{
target_ulong save_r2 = 0;
target_ulong msr;
target_ulong xer;
target_ulong ccr;
int i;
@ -330,9 +331,11 @@ static void restore_user_regs(CPUPPCState *env,
__get_user(env->nip, &frame->mc_gregs[TARGET_PT_NIP]);
__get_user(env->ctr, &frame->mc_gregs[TARGET_PT_CTR]);
__get_user(env->lr, &frame->mc_gregs[TARGET_PT_LNK]);
__get_user(env->xer, &frame->mc_gregs[TARGET_PT_XER]);
__get_user(ccr, &frame->mc_gregs[TARGET_PT_CCR]);
__get_user(xer, &frame->mc_gregs[TARGET_PT_XER]);
cpu_write_xer(env, xer);
__get_user(ccr, &frame->mc_gregs[TARGET_PT_CCR]);
for (i = 0; i < ARRAY_SIZE(env->crf); i++) {
env->crf[i] = (ccr >> (32 - ((i + 1) * 4))) & 0xf;
}

2
tests/tcg/ppc64/Makefile.target
View File

@ -23,4 +23,6 @@ run-plugin-byte_reverse-with-%:
$(call skip-test, "RUN of byte_reverse ($*)", "not built")
endif
PPC64_TESTS += signal_save_restore_xer
TESTS += $(PPC64_TESTS)

2
tests/tcg/ppc64le/Makefile.target
View File

@ -22,4 +22,6 @@ run-plugin-byte_reverse-with-%:
$(call skip-test, "RUN of byte_reverse ($*)", "not built")
endif
PPC64LE_TESTS += signal_save_restore_xer
TESTS += $(PPC64LE_TESTS)

42
tests/tcg/ppc64le/signal_save_restore_xer.c Normal file
View File

@ -0,0 +1,42 @@
#include <assert.h>
#include <stdint.h>
#include <signal.h>
#include <sys/user.h>
#define XER_SO (1 << 31)
#define XER_OV (1 << 30)
#define XER_CA (1 << 29)
#define XER_OV32 (1 << 19)
#define XER_CA32 (1 << 18)
uint64_t saved;
void sigill_handler(int sig, siginfo_t *si, void *ucontext)
{
ucontext_t *uc = ucontext;
uc->uc_mcontext.regs->nip += 4;
saved = uc->uc_mcontext.regs->xer;
uc->uc_mcontext.regs->xer |= XER_OV | XER_OV32;
}
int main(void)
{
uint64_t initial = XER_CA | XER_CA32, restored;
struct sigaction sa = {
.sa_sigaction = sigill_handler,
.sa_flags = SA_SIGINFO
};
sigaction(SIGILL, &sa, NULL);
asm("mtspr 1, %1\n\t"
".long 0x0\n\t"
"mfspr %0, 1\n\t"
: "=r" (restored)
: "r" (initial));
assert(saved == initial);
assert(restored == (XER_OV | XER_OV32 | XER_CA | XER_CA32));
return 0;
}