On Sat, Dec 10, 2022 at 07:27:46AM -0800, Guenter Roeck wrote: > Hi, > > On Thu, Sep 01, 2022 at 11:15:09AM +0100, Richard Henderson wrote: > > The value previously chosen overlaps GUSA_MASK. > > > > Rename all DELAY_SLOT_* and GUSA_* defines to emphasize > > that they are included in TB_FLAGs. Add aliases for the > > FPSCR and SR bits that are included in TB_FLAGS, so that > > we don't accidentally reassign those bits. > > > > Fixes: 4da06fb3062 ("target/sh4: Implement prctl_unalign_sigbus") > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/856 > > Signed-off-by: Richard Henderson <richard.hender...@linaro.org> > > I noticed that my sh4 emulations crash randomly with qemu v7.2-rc4. > This happens with all Linux kernel versions. Testing shows that this > patch is responsible. Reverting it fixes the problem. >
The patch below fixes the problem for me. Guenter --- >From d488bcad383f360e522dbffe0d21f8ad39d33c61 Mon Sep 17 00:00:00 2001 From: Guenter Roeck <li...@roeck-us.net> Date: Sun, 11 Dec 2022 14:14:47 -0800 Subject: [PATCH] target/sh4: Fix unaligned handling Commit ab419fd8a035 ("target/sh4: Fix TB_FLAG_UNALIGN") made a number of changes which seemed unrelated to the problem being fixed. In addition to updating updating masks, it eliminated various mask operations. This results in a number of inexplicable crashes, often associated with alleged unaligned operations. Improve alignment with the original code. Reintroduce mask operations, and undo an added '#ifdef CONFIG_USER_ONLY'. While I have no real idea what I am doing, the resulting code no longer crashes, so it must do some good. Fixes: ab419fd8a035 ("target/sh4: Fix TB_FLAG_UNALIGN") Signed-off-by: Guenter Roeck <li...@roeck-us.net> --- linux-user/sh4/signal.c | 2 +- target/sh4/cpu.c | 2 +- target/sh4/translate.c | 2 -- 3 files changed, 2 insertions(+), 4 deletions(-) diff --git a/linux-user/sh4/signal.c b/linux-user/sh4/signal.c index c4ba962708..2135e2b881 100644 --- a/linux-user/sh4/signal.c +++ b/linux-user/sh4/signal.c @@ -161,7 +161,7 @@ static void restore_sigcontext(CPUSH4State *regs, struct target_sigcontext *sc) __get_user(regs->fpul, &sc->sc_fpul); regs->tra = -1; /* disable syscall checks */ - regs->flags = 0; + regs->flags &= ~(TB_FLAG_DELAY_SLOT_MASK | TB_FLAG_GUSA_MASK); } void setup_frame(int sig, struct target_sigaction *ka, diff --git a/target/sh4/cpu.c b/target/sh4/cpu.c index 453268392b..827cee25af 100644 --- a/target/sh4/cpu.c +++ b/target/sh4/cpu.c @@ -47,7 +47,7 @@ static void superh_cpu_synchronize_from_tb(CPUState *cs, SuperHCPU *cpu = SUPERH_CPU(cs); cpu->env.pc = tb_pc(tb); - cpu->env.flags = tb->flags; + cpu->env.flags = tb->flags & TB_FLAG_ENVFLAGS_MASK; } static void superh_restore_state_to_opc(CPUState *cs, diff --git a/target/sh4/translate.c b/target/sh4/translate.c index 7db3468b01..546c182463 100644 --- a/target/sh4/translate.c +++ b/target/sh4/translate.c @@ -2270,7 +2270,6 @@ static void sh4_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) (tbflags & (1 << SR_RB))) * 0x10; ctx->fbank = tbflags & FPSCR_FR ? 0x10 : 0; -#ifdef CONFIG_USER_ONLY if (tbflags & TB_FLAG_GUSA_MASK) { /* In gUSA exclusive region. */ uint32_t pc = ctx->base.pc_next; @@ -2290,7 +2289,6 @@ static void sh4_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs) return; } } -#endif /* Since the ISA is fixed-width, we can bound by the number of instructions remaining on the page. */ -- 2.36.2