Previously we just saved the FSCR, but only restored it in some settings, and never copied it thread to thread. This patch always restores the FSCR and formalizes new threads inheriting its setting so that later we can manipulate FSCR bits in start_thread.
Signed-off-by: Jack Miller <j...@codezen.org> --- arch/powerpc/kernel/process.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index b8500b4..00bf6f5 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -1019,18 +1019,12 @@ static inline void restore_sprs(struct thread_struct *old_thread, #ifdef CONFIG_PPC_BOOK3S_64 if (cpu_has_feature(CPU_FTR_DSCR)) { u64 dscr = get_paca()->dscr_default; - u64 fscr = old_thread->fscr & ~FSCR_DSCR; - if (new_thread->dscr_inherit) { + if (new_thread->dscr_inherit) dscr = new_thread->dscr; - fscr |= FSCR_DSCR; - } if (old_thread->dscr != dscr) mtspr(SPRN_DSCR, dscr); - - if (old_thread->fscr != fscr) - mtspr(SPRN_FSCR, fscr); } if (cpu_has_feature(CPU_FTR_ARCH_207S)) { @@ -1041,6 +1035,9 @@ static inline void restore_sprs(struct thread_struct *old_thread, if (old_thread->ebbrr != new_thread->ebbrr) mtspr(SPRN_EBBRR, new_thread->ebbrr); + if (old_thread->fscr != new_thread->fscr) + mtspr(SPRN_FSCR, new_thread->fscr); + if (old_thread->tar != new_thread->tar) mtspr(SPRN_TAR, new_thread->tar); } @@ -1478,6 +1475,9 @@ int copy_thread(unsigned long clone_flags, unsigned long usp, } if (cpu_has_feature(CPU_FTR_HAS_PPR)) p->thread.ppr = INIT_PPR; + + if (cpu_has_feature(CPU_FTR_ARCH_207S)) + p->thread.fscr = mfspr(SPRN_FSCR); #endif kregs->nip = ppc_function_entry(f); return 0; -- 2.8.0 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev