From ab8bab68bba3e0c58428249f8b467b93adf98c07 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Thu, 5 Sep 2019 11:32:06 +0200 Subject: [PATCH] s390x/tcg: MVN: Fault-safe handling We can process a maximum of 256 bytes, crossing two pages. Reviewed-by: Richard Henderson Signed-off-by: David Hildenbrand --- target/s390x/mem_helper.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c index eeb2552979..7c981f7902 100644 --- a/target/s390x/mem_helper.c +++ b/target/s390x/mem_helper.c @@ -500,13 +500,22 @@ void HELPER(mvcin)(CPUS390XState *env, uint32_t l, uint64_t dest, uint64_t src) /* move numerics */ void HELPER(mvn)(CPUS390XState *env, uint32_t l, uint64_t dest, uint64_t src) { + const int mmu_idx = cpu_mmu_index(env, false); + S390Access srca1, srca2, desta; uintptr_t ra = GETPC(); int i; - for (i = 0; i <= l; i++) { - uint8_t v = cpu_ldub_data_ra(env, dest + i, ra) & 0xf0; - v |= cpu_ldub_data_ra(env, src + i, ra) & 0x0f; - cpu_stb_data_ra(env, dest + i, v, ra); + /* MVN always copies one more byte than specified - maximum is 256 */ + l++; + + srca1 = access_prepare(env, src, l, MMU_DATA_LOAD, mmu_idx, ra); + srca2 = access_prepare(env, dest, l, MMU_DATA_LOAD, mmu_idx, ra); + desta = access_prepare(env, dest, l, MMU_DATA_STORE, mmu_idx, ra); + for (i = 0; i < l; i++) { + const uint8_t x = (access_get_byte(env, &srca1, i, ra) & 0x0f) | + (access_get_byte(env, &srca2, i, ra) & 0xf0); + + access_set_byte(env, &desta, i, x, ra); } }