From bace1f90f9207ec79e9d28eb668532b43ac8b81f Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Sat, 3 Jun 2017 02:11:13 -0700 Subject: [PATCH] target/xtensa: handle unknown registers in gdbstub Xtensa cores may have registers of types/sizes not supported by the gdbstub accessors. Ignore writes to such registers and return zero on read, but always return correct register size, so that gdb on the other side is able to access all registers in the packet holding unsupported registers in the middle. This fixes gdb interaction with cores that have vector/custom TIE registers. Cc: qemu-stable@nongnu.org Signed-off-by: Max Filippov (cherry picked from commit dd7b952b793e341c905355581a21cdbaa8b13c31) Signed-off-by: Michael Roth --- target/xtensa/gdbstub.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/target/xtensa/gdbstub.c b/target/xtensa/gdbstub.c index fa5469a4ef..da131ae8cc 100644 --- a/target/xtensa/gdbstub.c +++ b/target/xtensa/gdbstub.c @@ -58,7 +58,10 @@ int xtensa_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n) case 8: return gdb_get_reg64(mem_buf, float64_val(env->fregs[i].f64)); default: - return 0; + qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported size %d\n", + __func__, n, reg->size); + memset(mem_buf, 0, reg->size); + return reg->size; } case 8: /*a*/ @@ -67,6 +70,8 @@ int xtensa_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n) default: qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported type %d\n", __func__, n, reg->type); + memset(mem_buf, 0, reg->size); + return reg->size; return 0; } } @@ -111,7 +116,9 @@ int xtensa_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) env->fregs[reg->targno & 0x0f].f64 = make_float64(tmp); return 8; default: - return 0; + qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported size %d\n", + __func__, n, reg->size); + return reg->size; } case 8: /*a*/ @@ -121,7 +128,7 @@ int xtensa_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) default: qemu_log_mask(LOG_UNIMP, "%s to reg %d of unsupported type %d\n", __func__, n, reg->type); - return 0; + return reg->size; } return 4; -- 2.39.2