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| author | Huacai Chen <chenhuacai@loongson.cn> | 2024-11-12 16:35:39 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-11-22 15:39:53 +0100 |
| commit | 4f000bdb3789d8f43adfd73510e3748557b2eef2 (patch) | |
| tree | 0a7adaf7d3f618342a722a3f942a2cfe51b8d36a | |
| parent | 4e8dbf5a6558ae4132a11cdb82e71538702a1f82 (diff) | |
| download | linux-stable-4f000bdb3789d8f43adfd73510e3748557b2eef2.tar.gz linux-stable-4f000bdb3789d8f43adfd73510e3748557b2eef2.tar.bz2 linux-stable-4f000bdb3789d8f43adfd73510e3748557b2eef2.zip | |
LoongArch: Make KASAN work with 5-level page-tables
commit a410656643ce4844ba9875aa4e87a7779308259b upstream.
Make KASAN work with 5-level page-tables, including:
1. Implement and use __pgd_none() and kasan_p4d_offset().
2. As done in kasan_pmd_populate() and kasan_pte_populate(), restrict
the loop conditions of kasan_p4d_populate() and kasan_pud_populate()
to avoid unnecessary population.
Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/loongarch/mm/kasan_init.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/arch/loongarch/mm/kasan_init.c b/arch/loongarch/mm/kasan_init.c index ff54c954e019..d2681272d8f0 100644 --- a/arch/loongarch/mm/kasan_init.c +++ b/arch/loongarch/mm/kasan_init.c @@ -13,6 +13,13 @@ static pgd_t kasan_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); +#ifdef __PAGETABLE_P4D_FOLDED +#define __pgd_none(early, pgd) (0) +#else +#define __pgd_none(early, pgd) (early ? (pgd_val(pgd) == 0) : \ +(__pa(pgd_val(pgd)) == (unsigned long)__pa(kasan_early_shadow_p4d))) +#endif + #ifdef __PAGETABLE_PUD_FOLDED #define __p4d_none(early, p4d) (0) #else @@ -147,6 +154,19 @@ static pud_t *__init kasan_pud_offset(p4d_t *p4dp, unsigned long addr, int node, return pud_offset(p4dp, addr); } +static p4d_t *__init kasan_p4d_offset(pgd_t *pgdp, unsigned long addr, int node, bool early) +{ + if (__pgd_none(early, pgdp_get(pgdp))) { + phys_addr_t p4d_phys = early ? + __pa_symbol(kasan_early_shadow_p4d) : kasan_alloc_zeroed_page(node); + if (!early) + memcpy(__va(p4d_phys), kasan_early_shadow_p4d, sizeof(kasan_early_shadow_p4d)); + pgd_populate(&init_mm, pgdp, (p4d_t *)__va(p4d_phys)); + } + + return p4d_offset(pgdp, addr); +} + static void __init kasan_pte_populate(pmd_t *pmdp, unsigned long addr, unsigned long end, int node, bool early) { @@ -183,19 +203,19 @@ static void __init kasan_pud_populate(p4d_t *p4dp, unsigned long addr, do { next = pud_addr_end(addr, end); kasan_pmd_populate(pudp, addr, next, node, early); - } while (pudp++, addr = next, addr != end); + } while (pudp++, addr = next, addr != end && __pud_none(early, READ_ONCE(*pudp))); } static void __init kasan_p4d_populate(pgd_t *pgdp, unsigned long addr, unsigned long end, int node, bool early) { unsigned long next; - p4d_t *p4dp = p4d_offset(pgdp, addr); + p4d_t *p4dp = kasan_p4d_offset(pgdp, addr, node, early); do { next = p4d_addr_end(addr, end); kasan_pud_populate(p4dp, addr, next, node, early); - } while (p4dp++, addr = next, addr != end); + } while (p4dp++, addr = next, addr != end && __p4d_none(early, READ_ONCE(*p4dp))); } static void __init kasan_pgd_populate(unsigned long addr, unsigned long end, |