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author | James Morse <james.morse@arm.com> | 2021-11-18 16:04:32 +0100 |
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committer | James Morse <james.morse@arm.com> | 2022-02-15 18:40:28 +0100 |
commit | a9c406e6462ff14956d690de7bbe5131a5677dc9 (patch) | |
tree | 90b8435c09994d03fff2d8d26d131c503efdd700 /arch/arm64/mm/mmu.c | |
parent | arm64: entry: Make the kpti trampoline's kpti sequence optional (diff) | |
download | linux-a9c406e6462ff14956d690de7bbe5131a5677dc9.tar.xz linux-a9c406e6462ff14956d690de7bbe5131a5677dc9.zip |
arm64: entry: Allow the trampoline text to occupy multiple pages
Adding a second set of vectors to .entry.tramp.text will make it
larger than a single 4K page.
Allow the trampoline text to occupy up to three pages by adding two
more fixmap slots. Previous changes to tramp_valias allowed it to reach
beyond a single page.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Diffstat (limited to 'arch/arm64/mm/mmu.c')
-rw-r--r-- | arch/arm64/mm/mmu.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index acfae9b41cc8..49abbf43bf35 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -617,6 +617,8 @@ early_param("rodata", parse_rodata); #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 static int __init map_entry_trampoline(void) { + int i; + pgprot_t prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC; phys_addr_t pa_start = __pa_symbol(__entry_tramp_text_start); @@ -625,11 +627,15 @@ static int __init map_entry_trampoline(void) /* Map only the text into the trampoline page table */ memset(tramp_pg_dir, 0, PGD_SIZE); - __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, PAGE_SIZE, - prot, __pgd_pgtable_alloc, 0); + __create_pgd_mapping(tramp_pg_dir, pa_start, TRAMP_VALIAS, + entry_tramp_text_size(), prot, + __pgd_pgtable_alloc, NO_BLOCK_MAPPINGS); /* Map both the text and data into the kernel page table */ - __set_fixmap(FIX_ENTRY_TRAMP_TEXT, pa_start, prot); + for (i = 0; i < DIV_ROUND_UP(entry_tramp_text_size(), PAGE_SIZE); i++) + __set_fixmap(FIX_ENTRY_TRAMP_TEXT1 - i, + pa_start + i * PAGE_SIZE, prot); + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { extern char __entry_tramp_data_start[]; |