From 2a0fb3c155c97c75176e557d61f8e66c1bd9b735 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 14 Jun 2022 12:34:09 +0200 Subject: powerpc/32: Set an IBAT covering up to _einittext during init 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 Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/ce7f04a39593934d9b1ee68c69144ccd3d4da4a1.1655202804.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/book3s32/mmu.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'arch/powerpc/mm') diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c index 1794132db31e..a96b73006dfb 100644 --- a/arch/powerpc/mm/book3s32/mmu.c +++ b/arch/powerpc/mm/book3s32/mmu.c @@ -159,7 +159,10 @@ 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()) { pr_debug_once("Read-Write memory mapped without BATs\n"); @@ -245,10 +248,9 @@ 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) @@ -284,10 +286,6 @@ 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; -- cgit v1.2.3