When a LWL, LWR, LDL or LDR instruction triggers a page fault, QEMU currently reports the aligned address in CP0 BadVAddr, while the Windows NT kernel expects the unaligned address.
This patch adds a byte access with the unaligned address at the beginning of the LWL/LWR/LDL/LDR instructions to possibly trigger a page fault and fill the QEMU TLB. Cc: Leon Alrae <leon.al...@imgtec.com> Reported-by: Hervé Poussineau <hpous...@reactos.org> Tested-by: Hervé Poussineau <hpous...@reactos.org> Signed-off-by: Aurelien Jarno <aurel...@aurel32.net> --- target-mips/translate.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/target-mips/translate.c b/target-mips/translate.c index 7302857..0ac3bd8 100644 --- a/target-mips/translate.c +++ b/target-mips/translate.c @@ -2142,6 +2142,9 @@ static void gen_ld(DisasContext *ctx, uint32_t opc, break; case OPC_LDL: t1 = tcg_temp_new(); + /* Do a byte access to possibly trigger a page + fault with the unaligned address. */ + tcg_gen_qemu_ld_tl(t1, t0, ctx->mem_idx, MO_UB); tcg_gen_andi_tl(t1, t0, 7); #ifndef TARGET_WORDS_BIGENDIAN tcg_gen_xori_tl(t1, t1, 7); @@ -2163,6 +2166,9 @@ static void gen_ld(DisasContext *ctx, uint32_t opc, break; case OPC_LDR: t1 = tcg_temp_new(); + /* Do a byte access to possibly trigger a page + fault with the unaligned address. */ + tcg_gen_qemu_ld_tl(t1, t0, ctx->mem_idx, MO_UB); tcg_gen_andi_tl(t1, t0, 7); #ifdef TARGET_WORDS_BIGENDIAN tcg_gen_xori_tl(t1, t1, 7); @@ -2229,6 +2235,9 @@ static void gen_ld(DisasContext *ctx, uint32_t opc, break; case OPC_LWL: t1 = tcg_temp_new(); + /* Do a byte access to possibly trigger a page + fault with the unaligned address. */ + tcg_gen_qemu_ld_tl(t1, t0, ctx->mem_idx, MO_UB); tcg_gen_andi_tl(t1, t0, 3); #ifndef TARGET_WORDS_BIGENDIAN tcg_gen_xori_tl(t1, t1, 3); @@ -2251,6 +2260,9 @@ static void gen_ld(DisasContext *ctx, uint32_t opc, break; case OPC_LWR: t1 = tcg_temp_new(); + /* Do a byte access to possibly trigger a page + fault with the unaligned address. */ + tcg_gen_qemu_ld_tl(t1, t0, ctx->mem_idx, MO_UB); tcg_gen_andi_tl(t1, t0, 3); #ifdef TARGET_WORDS_BIGENDIAN tcg_gen_xori_tl(t1, t1, 3); -- 2.1.4