| Message ID | 20191025113921.9412-12-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | linux-user sparc fixes | expand |
Le 25/10/2019 à 13:39, Richard Henderson a écrit : > We failed to set the secondary return value in %o1 > we failed to advance the PC past the syscall, > we failed to adjust regwptr into the new structure, > we stored the stack pointer into the wrong register. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > v2: Take CLONE_VM into account when performing syscall return. > --- > linux-user/sparc/target_cpu.h | 47 ++++++++++++++++++++++++++++------- > 1 file changed, 38 insertions(+), 9 deletions(-) > > diff --git a/linux-user/sparc/target_cpu.h b/linux-user/sparc/target_cpu.h > index 8ff706adce..14b2158969 100644 > --- a/linux-user/sparc/target_cpu.h > +++ b/linux-user/sparc/target_cpu.h > @@ -23,22 +23,51 @@ > static inline void cpu_clone_regs_child(CPUSPARCState *env, target_ulong newsp, > unsigned flags) > { > - if (newsp) { > - env->regwptr[22] = newsp; > - } > - /* syscall return for clone child: 0, and clear CF since > - * this counts as a success return value. > + /* > + * After cpu_copy, env->regwptr is pointing into the old env. > + * Update the new cpu to use its own register window. > */ > - env->regwptr[0] = 0; > -#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) > - env->xcc &= ~PSR_CARRY; > + env->regwptr = env->regbase + (env->cwp * 16); > + > + if (newsp) { > + /* When changing stacks, do it with clean register windows. */ > +#ifdef TARGET_SPARC64 > + env->cansave = env->nwindows - 2; > + env->cleanwin = env->nwindows - 2; > + env->canrestore = 0; > #else > - env->psr &= ~PSR_CARRY; > + env->wim = 1 << env->cwp; > #endif > + /* ??? The kernel appears to copy one stack frame to the new stack. */ > + /* ??? The kernel force aligns the new stack. */ > + env->regwptr[WREG_SP] = newsp; > + } > + > + if (flags & CLONE_VM) { > + /* > + * Syscall return for clone child: %o0 = 0 and clear CF since this > + * counts as a success return value. Advance the PC past the syscall. > + * For fork child, all of this happens in cpu_loop, and we must not > + * do the pc advance twice. > + */ > + env->regwptr[WREG_O0] = 0; > +#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) > + env->xcc &= ~PSR_CARRY; > +#else > + env->psr &= ~PSR_CARRY; > +#endif > + env->pc = env->npc; > + env->npc = env->npc + 4; > + } > + > + /* Set the second return value for the child: %o1 = 1. */ > + env->regwptr[WREG_O1] = 1; > } > > static inline void cpu_clone_regs_parent(CPUSPARCState *env, unsigned flags) > { > + /* Set the second return value for the parent: %o1 = 0. */ > + env->regwptr[WREG_O1] = 0; > } > > static inline void cpu_set_tls(CPUSPARCState *env, target_ulong newtls) > Applied to my linux-user branch. Thanks, Laurent
diff --git a/linux-user/sparc/target_cpu.h b/linux-user/sparc/target_cpu.h index 8ff706adce..14b2158969 100644 --- a/linux-user/sparc/target_cpu.h +++ b/linux-user/sparc/target_cpu.h @@ -23,22 +23,51 @@ static inline void cpu_clone_regs_child(CPUSPARCState *env, target_ulong newsp, unsigned flags) { - if (newsp) { - env->regwptr[22] = newsp; - } - /* syscall return for clone child: 0, and clear CF since - * this counts as a success return value. + /* + * After cpu_copy, env->regwptr is pointing into the old env. + * Update the new cpu to use its own register window. */ - env->regwptr[0] = 0; -#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) - env->xcc &= ~PSR_CARRY; + env->regwptr = env->regbase + (env->cwp * 16); + + if (newsp) { + /* When changing stacks, do it with clean register windows. */ +#ifdef TARGET_SPARC64 + env->cansave = env->nwindows - 2; + env->cleanwin = env->nwindows - 2; + env->canrestore = 0; #else - env->psr &= ~PSR_CARRY; + env->wim = 1 << env->cwp; #endif + /* ??? The kernel appears to copy one stack frame to the new stack. */ + /* ??? The kernel force aligns the new stack. */ + env->regwptr[WREG_SP] = newsp; + } + + if (flags & CLONE_VM) { + /* + * Syscall return for clone child: %o0 = 0 and clear CF since this + * counts as a success return value. Advance the PC past the syscall. + * For fork child, all of this happens in cpu_loop, and we must not + * do the pc advance twice. + */ + env->regwptr[WREG_O0] = 0; +#if defined(TARGET_SPARC64) && !defined(TARGET_ABI32) + env->xcc &= ~PSR_CARRY; +#else + env->psr &= ~PSR_CARRY; +#endif + env->pc = env->npc; + env->npc = env->npc + 4; + } + + /* Set the second return value for the child: %o1 = 1. */ + env->regwptr[WREG_O1] = 1; } static inline void cpu_clone_regs_parent(CPUSPARCState *env, unsigned flags) { + /* Set the second return value for the parent: %o1 = 0. */ + env->regwptr[WREG_O1] = 0; } static inline void cpu_set_tls(CPUSPARCState *env, target_ulong newtls)
We failed to set the secondary return value in %o1 we failed to advance the PC past the syscall, we failed to adjust regwptr into the new structure, we stored the stack pointer into the wrong register. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- v2: Take CLONE_VM into account when performing syscall return. --- linux-user/sparc/target_cpu.h | 47 ++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 9 deletions(-) -- 2.17.1