From: Christophe Leroy christophe.leroy@csgroup.eu
[ Upstream commit 2a0fb3c155c97c75176e557d61f8e66c1bd9b735 ]
Always set an IBAT covering up to _einittext during init because when CONFIG_MODULES is not selected there is no reason to have an exception handler for kernel instruction TLB misses.
It implies DBAT and IBAT are now totaly independent, IBATs are set by setibat() and DBAT by setbat().
This allows to revert commit 9bb162fa26ed ("powerpc/603: Fix boot failure with DEBUG_PAGEALLOC and KFENCE")
Reported-by: Maxime Bizon mbizon@freebox.fr Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/ce7f04a39593934d9b1ee68c69144ccd3d4da4a1.165520280... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/kernel/head_book3s_32.S | 4 ++-- arch/powerpc/mm/book3s32/mmu.c | 10 ++++------ 2 files changed, 6 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S index 6c739beb938c..519b60695167 100644 --- a/arch/powerpc/kernel/head_book3s_32.S +++ b/arch/powerpc/kernel/head_book3s_32.S @@ -418,14 +418,14 @@ InstructionTLBMiss: */ /* Get PTE (linux-style) and check access */ mfspr r3,SPRN_IMISS -#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE) +#ifdef CONFIG_MODULES lis r1, TASK_SIZE@h /* check if kernel address */ cmplw 0,r1,r3 #endif mfspr r2, SPRN_SDR1 li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC | _PAGE_USER rlwinm r2, r2, 28, 0xfffff000 -#if defined(CONFIG_MODULES) || defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_KFENCE) +#ifdef CONFIG_MODULES bgt- 112f lis r2, (swapper_pg_dir - PAGE_OFFSET)@ha /* if kernel address, use */ li r1,_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_EXEC diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c index 203735caf691..bfca0afe9112 100644 --- a/arch/powerpc/mm/book3s32/mmu.c +++ b/arch/powerpc/mm/book3s32/mmu.c @@ -160,7 +160,10 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) { unsigned long done; unsigned long border = (unsigned long)__init_begin - PAGE_OFFSET; + unsigned long size;
+ size = roundup_pow_of_two((unsigned long)_einittext - PAGE_OFFSET); + setibat(0, PAGE_OFFSET, 0, size, PAGE_KERNEL_X);
if (debug_pagealloc_enabled_or_kfence() || __map_without_bats) { pr_debug_once("Read-Write memory mapped without BATs\n"); @@ -246,10 +249,9 @@ void mmu_mark_rodata_ro(void) }
/* - * Set up one of the I/D BAT (block address translation) register pairs. + * Set up one of the D BAT (block address translation) register pairs. * The parameters are not checked; in particular size must be a power * of 2 between 128k and 256M. - * On 603+, only set IBAT when _PAGE_EXEC is set */ void __init setbat(int index, unsigned long virt, phys_addr_t phys, unsigned int size, pgprot_t prot) @@ -285,10 +287,6 @@ void __init setbat(int index, unsigned long virt, phys_addr_t phys, /* G bit must be zero in IBATs */ flags &= ~_PAGE_EXEC; } - if (flags & _PAGE_EXEC) - bat[0] = bat[1]; - else - bat[0].batu = bat[0].batl = 0;
bat_addrs[index].start = virt; bat_addrs[index].limit = virt + ((bl + 1) << 17) - 1;