diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c index 7a7793211ae73c3ffe0c56fdbc1d4c006bd041f8..7e12ef70808f7d80d87f58828d0f34fa73909094 100644 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ b/arch/powerpc/kernel/machine_kexec_64.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include /* _end */ @@ -64,31 +65,6 @@ int default_machine_kexec_prepare(struct kimage *image) if (image->segment[i].mem < __pa(_end)) return -ETXTBSY; - /* - * For non-LPAR, we absolutely can not overwrite the mmu hash - * table, since we are still using the bolted entries in it to - * do the copy. Check that here. - * - * It is safe if the end is below the start of the blocked - * region (end <= low), or if the beginning is after the - * end of the blocked region (begin >= high). Use the - * boolean identity !(a || b) === (!a && !b). - */ -#ifdef CONFIG_PPC_STD_MMU_64 - if (htab_address) { - low = __pa(htab_address); - high = low + htab_size_bytes; - - for (i = 0; i < image->nr_segments; i++) { - begin = image->segment[i].mem; - end = begin + image->segment[i].memsz; - - if ((begin < high) && (end > low)) - return -ETXTBSY; - } - } -#endif /* CONFIG_PPC_STD_MMU_64 */ - /* We also should not overwrite the tce tables */ for_each_node_by_type(node, "pci") { basep = of_get_property(node, "linux,tce-base", NULL); @@ -329,11 +305,14 @@ struct paca_struct kexec_paca; /* Our assembly helper, in misc_64.S */ extern void kexec_sequence(void *newstack, unsigned long start, void *image, void *control, - void (*clear_all)(void)) __noreturn; + void (*clear_all)(void), + bool copy_with_mmu_off) __noreturn; /* too late to fail here */ void default_machine_kexec(struct kimage *image) { + bool copy_with_mmu_off; + /* prepare control code if any */ /* @@ -371,13 +350,29 @@ void default_machine_kexec(struct kimage *image) /* XXX: If anyone does 'dynamic lppacas' this will also need to be * switched to a static version! */ + /* + * On Book3S, the copy must happen with the MMU off if we are either + * using Radix page tables or we are not in an LPAR since we can + * overwrite the page tables while copying. + * + * In an LPAR, we keep the MMU on otherwise we can't access beyond + * the RMA. On BookE there is no real MMU off mode, so we have to + * keep it enabled as well (but then we have bolted TLB entries). + */ +#ifdef CONFIG_PPC_BOOK3E + copy_with_mmu_off = false; +#else + copy_with_mmu_off = radix_enabled() || + !(firmware_has_feature(FW_FEATURE_LPAR) || + firmware_has_feature(FW_FEATURE_PS3_LV1)); +#endif /* Some things are best done in assembly. Finding globals with * a toc is easier in C, so pass in what we can. */ kexec_sequence(&kexec_stack, image->start, image, page_address(image->control_code_page), - mmu_cleanup_all); + mmu_cleanup_all, copy_with_mmu_off); /* NOTREACHED */ } diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 939e3f50a345fe080539b97b429249a24e36779c..9f0bed214bcb891d48078cfa094c3c1792a3a0d3 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -592,7 +592,8 @@ real_mode: /* assume normal blr return */ #endif /* - * kexec_sequence(newstack, start, image, control, clear_all()) + * kexec_sequence(newstack, start, image, control, clear_all(), + copy_with_mmu_off) * * does the grungy work with stack switching and real mode switches * also does simple calls to other code @@ -628,7 +629,7 @@ _GLOBAL(kexec_sequence) mr r29,r5 /* image (virt) */ mr r28,r6 /* control, unused */ mr r27,r7 /* clear_all() fn desc */ - mr r26,r8 /* spare */ + mr r26,r8 /* copy_with_mmu_off */ lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */ /* disable interrupts, we are overwriting kernel data next */ @@ -640,15 +641,24 @@ _GLOBAL(kexec_sequence) mtmsrd r3,1 #endif + /* We need to turn the MMU off unless we are in hash mode + * under a hypervisor + */ + cmpdi r26,0 + beq 1f + bl real_mode +1: /* copy dest pages, flush whole dest image */ mr r3,r29 bl kexec_copy_flush /* (image) */ - /* turn off mmu */ + /* turn off mmu now if not done earlier */ + cmpdi r26,0 + bne 1f bl real_mode /* copy 0x100 bytes starting at start to 0 */ - li r3,0 +1: li r3,0 mr r4,r30 /* start, aka phys mem offset */ li r5,0x100 li r6,0