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author | Mark Rutland <mark.rutland@arm.com> | 2023-04-06 18:27:57 +0300 |
---|---|---|
committer | Will Deacon <will@kernel.org> | 2023-04-11 20:55:28 +0300 |
commit | 32f5b6995f790ac8fc048d3afd6b83c82074aedf (patch) | |
tree | 3190a7abf458bf722421bd0a993c673d769385ce /arch/arm64/mm | |
parent | 7bd6680b47fa4cd53ee1047693c09825e212a6f5 (diff) | |
download | linux-32f5b6995f790ac8fc048d3afd6b83c82074aedf.tar.xz |
arm64: add FIXADDR_TOT_{START,SIZE}
Currently arm64's FIXADDR_{START,SIZE} definitions only cover the
runtime fixmap slots (and not the boot-time fixmap slots), but the code
for creating the fixmap assumes that these definitions cover the entire
fixmap range. This means that the ptdump boundaries are reported in a
misleading way, missing the VA region of the runtime slots. In theory
this could also cause the fixmap creation to go wrong if the boot-time
fixmap slots end up spilling into a separate PMD entry, though luckily
this is not currently the case in any configuration.
While it seems like we could extend FIXADDR_{START,SIZE} to cover the
entire fixmap area, core code relies upon these *only* covering the
runtime slots. For example, fix_to_virt() and virt_to_fix() try to
reject manipulation of the boot-time slots based upon
FIXADDR_{START,SIZE}, while __fix_to_virt() and __virt_to_fix() can
handle any fixmap slot.
This patch follows the lead of x86 in commit:
55f49fcb879fbeeb ("x86/mm: Fix overlap of i386 CPU_ENTRY_AREA with FIX_BTMAP")
... and add new FIXADDR_TOT_{START,SIZE} definitions which cover the
entire fixmap area, using these for the fixmap creation and ptdump code.
As the boot-time fixmap slots are now rejected by fix_to_virt(),
the early_fixmap_init() code is changed to consistently use
__fix_to_virt(), as it already does in a few cases.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Link: https://lore.kernel.org/r/20230406152759.4164229-2-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/mm')
-rw-r--r-- | arch/arm64/mm/mmu.c | 26 | ||||
-rw-r--r-- | arch/arm64/mm/ptdump.c | 2 |
2 files changed, 14 insertions, 14 deletions
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 9813f2a9c825..44954251e14d 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -795,14 +795,14 @@ static void __init map_kernel(pgd_t *pgdp) &vmlinux_initdata, 0, VM_NO_GUARD); map_kernel_segment(pgdp, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0); - if (!READ_ONCE(pgd_val(*pgd_offset_pgd(pgdp, FIXADDR_START)))) { + if (!READ_ONCE(pgd_val(*pgd_offset_pgd(pgdp, FIXADDR_TOT_START)))) { /* * The fixmap falls in a separate pgd to the kernel, and doesn't * live in the carveout for the swapper_pg_dir. We can simply * re-use the existing dir for the fixmap. */ - set_pgd(pgd_offset_pgd(pgdp, FIXADDR_START), - READ_ONCE(*pgd_offset_k(FIXADDR_START))); + set_pgd(pgd_offset_pgd(pgdp, FIXADDR_TOT_START), + READ_ONCE(*pgd_offset_k(FIXADDR_TOT_START))); } else if (CONFIG_PGTABLE_LEVELS > 3) { pgd_t *bm_pgdp; p4d_t *bm_p4dp; @@ -814,9 +814,9 @@ static void __init map_kernel(pgd_t *pgdp) * entry instead. */ BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES)); - bm_pgdp = pgd_offset_pgd(pgdp, FIXADDR_START); - bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_START); - bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_START); + bm_pgdp = pgd_offset_pgd(pgdp, FIXADDR_TOT_START); + bm_p4dp = p4d_offset(bm_pgdp, FIXADDR_TOT_START); + bm_pudp = pud_set_fixmap_offset(bm_p4dp, FIXADDR_TOT_START); pud_populate(&init_mm, bm_pudp, lm_alias(bm_pmd)); pud_clear_fixmap(); } else { @@ -1275,7 +1275,7 @@ void __init early_fixmap_init(void) p4d_t *p4dp, p4d; pud_t *pudp; pmd_t *pmdp; - unsigned long addr = FIXADDR_START; + unsigned long addr = FIXADDR_TOT_START; pgdp = pgd_offset_k(addr); p4dp = p4d_offset(pgdp, addr); @@ -1306,16 +1306,16 @@ void __init early_fixmap_init(void) BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); - if ((pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN))) - || pmdp != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) { + if ((pmdp != fixmap_pmd(__fix_to_virt(FIX_BTMAP_BEGIN))) + || pmdp != fixmap_pmd(__fix_to_virt(FIX_BTMAP_END))) { WARN_ON(1); pr_warn("pmdp %p != %p, %p\n", - pmdp, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)), - fixmap_pmd(fix_to_virt(FIX_BTMAP_END))); + pmdp, fixmap_pmd(__fix_to_virt(FIX_BTMAP_BEGIN)), + fixmap_pmd(__fix_to_virt(FIX_BTMAP_END))); pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", - fix_to_virt(FIX_BTMAP_BEGIN)); + __fix_to_virt(FIX_BTMAP_BEGIN)); pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", - fix_to_virt(FIX_BTMAP_END)); + __fix_to_virt(FIX_BTMAP_END)); pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c index 9bc4066c5bf3..e305b6593c4e 100644 --- a/arch/arm64/mm/ptdump.c +++ b/arch/arm64/mm/ptdump.c @@ -45,7 +45,7 @@ static struct addr_marker address_markers[] = { { MODULES_END, "Modules end" }, { VMALLOC_START, "vmalloc() area" }, { VMALLOC_END, "vmalloc() end" }, - { FIXADDR_START, "Fixmap start" }, + { FIXADDR_TOT_START, "Fixmap start" }, { FIXADDR_TOP, "Fixmap end" }, { PCI_IO_START, "PCI I/O start" }, { PCI_IO_END, "PCI I/O end" }, |