From 3afc6539a84d3d003025c9352a0596dbcb350ff4 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 10 Jul 2024 12:40:24 +0200 Subject: target/i386/tcg: fix POP to memory in long mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In long mode, POP to memory will write a full 64-bit value. However, the call to gen_writeback() in gen_POP will use MO_32 because the decoding table is incorrect. The bug was latent until commit aea49fbb01a ("target/i386: use gen_writeback() within gen_POP()", 2024-06-08), and then became visible because gen_op_st_v now receives op->ot instead of the "ot" returned by gen_pop_T0. Analyzed-by: Clément Chigot Fixes: 5e9e21bcc4d ("target/i386: move 60-BF opcodes to new decoder", 2024-05-07) Tested-by: Clément Chigot Reviewed-by: Richard Henderson Signed-off-by: Paolo Bonzini --- target/i386/tcg/decode-new.c.inc | 2 +- target/i386/tcg/emit.c.inc | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/target/i386/tcg/decode-new.c.inc b/target/i386/tcg/decode-new.c.inc index 0d846c32c2..d2da1d396d 100644 --- a/target/i386/tcg/decode-new.c.inc +++ b/target/i386/tcg/decode-new.c.inc @@ -1717,7 +1717,7 @@ static const X86OpEntry opcodes_root[256] = { [0x8C] = X86_OP_ENTRYwr(MOV, E,v, S,w, op0_Mw), [0x8D] = X86_OP_ENTRYwr(LEA, G,v, M,v, nolea), [0x8E] = X86_OP_ENTRYwr(MOV, S,w, E,w), - [0x8F] = X86_OP_GROUPw(group1A, E,v), + [0x8F] = X86_OP_GROUPw(group1A, E,d64), [0x98] = X86_OP_ENTRY1(CBW, 0,v), /* rAX */ [0x99] = X86_OP_ENTRYwr(CWD, 2,v, 0,v), /* rDX, rAX */ diff --git a/target/i386/tcg/emit.c.inc b/target/i386/tcg/emit.c.inc index fc7477833b..016dce8146 100644 --- a/target/i386/tcg/emit.c.inc +++ b/target/i386/tcg/emit.c.inc @@ -2788,6 +2788,7 @@ static void gen_POP(DisasContext *s, X86DecodedInsn *decode) X86DecodedOp *op = &decode->op[0]; MemOp ot = gen_pop_T0(s); + assert(ot >= op->ot); if (op->has_ea || op->unit == X86_OP_SEG) { /* NOTE: order is important for MMU exceptions */ gen_writeback(s, decode, 0, s->T0); -- cgit v1.2.3