On 5/25/26 08:23, Matt Turner wrote:
restore_user_regs() restores the PPC FPSCR with a direct assignment:env->fpscr = (uint32_t) fpscr; ppc_store_fpscr() exists precisely to write FPSCR and keep the derived env->fp_status in sync: it calls fpscr_set_rounding_mode() to update the softfloat rounding mode, and set_float_rebias_overflow/underflow() to reflect the FP_OE/FP_UE enable bits. The direct assignment bypasses all of this. On sigreturn, interrupted code resumes with whatever rounding mode and overflow/underflow-rebias state the signal handler last installed in fp_status, rather than the state that was saved at signal delivery. Replace the direct assign with ppc_store_fpscr(). The FPSCR_MTFS_MASK applied inside ppc_store_fpscr() only excludes the computed FP_FEX and FP_VX bits, which it re-derives correctly from the exception and enable bits in the restored value. Fixes: bcd4933a23 ("linux-user: ppc signal handling") Cc: [email protected] --- linux-user/ppc/signal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git ./linux-user/ppc/signal.c ./linux-user/ppc/signal.c index a9c10e0987..ab1afea30a 100644 --- ./linux-user/ppc/signal.c +++ ./linux-user/ppc/signal.c @@ -420,7 +420,7 @@ static void restore_user_regs(CPUPPCState *env, __get_user(*fpr, &frame->mc_fregs[i]); } __get_user(fpscr, &frame->mc_fregs[32]); - env->fpscr = (uint32_t) fpscr; + ppc_store_fpscr(env, (uint32_t) fpscr); }#if !defined(TARGET_PPC64)
I think the cast is wrong. With that dropped, Reviewed-by: Richard Henderson <[email protected]> r~
