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[2.7.42.160]) by smtp.gmail.com with ESMTPSA id t17-20020a0560001a5100b002bfb5618ee7sm1316284wry.91.2023.02.02.23.54.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Feb 2023 23:54:37 -0800 (PST) From: Alexandre Ghiti To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Andrey Ryabinin , Alexander Potapenko , Andrey Konovalov , Dmitry Vyukov , Vincenzo Frascino , Ard Biesheuvel , Conor Dooley , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-efi@vger.kernel.org Cc: Alexandre Ghiti Subject: [PATCH v4 2/6] riscv: Rework kasan population functions Date: Fri, 3 Feb 2023 08:52:28 +0100 Message-Id: <20230203075232.274282-3-alexghiti@rivosinc.com> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20230203075232.274282-1-alexghiti@rivosinc.com> References: <20230203075232.274282-1-alexghiti@rivosinc.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org Our previous kasan population implementation used to have the final kasan shadow region mapped with kasan_early_shadow_page, because we did not clean the early mapping and then we had to populate the kasan region "in-place" which made the code cumbersome. So now we clear the early mapping, establish a temporary mapping while we populate the kasan shadow region with just the kernel regions that will be used. This new version uses the "generic" way of going through a page table that may be folded at runtime (avoid the XXX_next macros). It was tested with outline instrumentation on an Ubuntu kernel configuration successfully. Signed-off-by: Alexandre Ghiti Reviewed-by: Björn Töpel --- arch/riscv/mm/kasan_init.c | 361 +++++++++++++++++++------------------ 1 file changed, 183 insertions(+), 178 deletions(-) diff --git a/arch/riscv/mm/kasan_init.c b/arch/riscv/mm/kasan_init.c index 2a48eba6bd08..8fc0efcf905c 100644 --- a/arch/riscv/mm/kasan_init.c +++ b/arch/riscv/mm/kasan_init.c @@ -18,58 +18,48 @@ * For sv39, the region is aligned on PGDIR_SIZE so we only need to populate * the page global directory with kasan_early_shadow_pmd. * - * For sv48 and sv57, the region is not aligned on PGDIR_SIZE so the mapping - * must be divided as follows: - * - the first PGD entry, although incomplete, is populated with - * kasan_early_shadow_pud/p4d - * - the PGD entries in the middle are populated with kasan_early_shadow_pud/p4d - * - the last PGD entry is shared with the kernel mapping so populated at the - * lower levels pud/p4d - * - * In addition, when shallow populating a kasan region (for example vmalloc), - * this region may also not be aligned on PGDIR size, so we must go down to the - * pud level too. + * For sv48 and sv57, the region start is aligned on PGDIR_SIZE whereas the end + * region is not and then we have to go down to the PUD level. */ extern pgd_t early_pg_dir[PTRS_PER_PGD]; +pgd_t tmp_pg_dir[PTRS_PER_PGD] __page_aligned_bss; +p4d_t tmp_p4d[PTRS_PER_P4D] __page_aligned_bss; +pud_t tmp_pud[PTRS_PER_PUD] __page_aligned_bss; static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end) { phys_addr_t phys_addr; - pte_t *ptep, *base_pte; + pte_t *ptep, *p; - if (pmd_none(*pmd)) - base_pte = memblock_alloc(PTRS_PER_PTE * sizeof(pte_t), PAGE_SIZE); - else - base_pte = (pte_t *)pmd_page_vaddr(*pmd); + if (pmd_none(*pmd)) { + p = memblock_alloc(PTRS_PER_PTE * sizeof(pte_t), PAGE_SIZE); + set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(p)), PAGE_TABLE)); + } - ptep = base_pte + pte_index(vaddr); + ptep = pte_offset_kernel(pmd, vaddr); do { if (pte_none(*ptep)) { phys_addr = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); set_pte(ptep, pfn_pte(PFN_DOWN(phys_addr), PAGE_KERNEL)); + memset(__va(phys_addr), KASAN_SHADOW_INIT, PAGE_SIZE); } } while (ptep++, vaddr += PAGE_SIZE, vaddr != end); - - set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(base_pte)), PAGE_TABLE)); } static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned long end) { phys_addr_t phys_addr; - pmd_t *pmdp, *base_pmd; + pmd_t *pmdp, *p; unsigned long next; if (pud_none(*pud)) { - base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE); - } else { - base_pmd = (pmd_t *)pud_pgtable(*pud); - if (base_pmd == lm_alias(kasan_early_shadow_pmd)) - base_pmd = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE); + p = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE); + set_pud(pud, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE)); } - pmdp = base_pmd + pmd_index(vaddr); + pmdp = pmd_offset(pud, vaddr); do { next = pmd_addr_end(vaddr, end); @@ -78,43 +68,28 @@ static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned phys_addr = memblock_phys_alloc(PMD_SIZE, PMD_SIZE); if (phys_addr) { set_pmd(pmdp, pfn_pmd(PFN_DOWN(phys_addr), PAGE_KERNEL)); + memset(__va(phys_addr), KASAN_SHADOW_INIT, PMD_SIZE); continue; } } kasan_populate_pte(pmdp, vaddr, next); } while (pmdp++, vaddr = next, vaddr != end); - - /* - * Wait for the whole PGD to be populated before setting the PGD in - * the page table, otherwise, if we did set the PGD before populating - * it entirely, memblock could allocate a page at a physical address - * where KASAN is not populated yet and then we'd get a page fault. - */ - set_pud(pud, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); } -static void __init kasan_populate_pud(pgd_t *pgd, +static void __init kasan_populate_pud(p4d_t *p4d, unsigned long vaddr, unsigned long end) { phys_addr_t phys_addr; - pud_t *pudp, *base_pud; + pud_t *pudp, *p; unsigned long next; - if (pgd_none(*pgd)) { - base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE); - memcpy(base_pud, (void *)kasan_early_shadow_pud, - sizeof(pud_t) * PTRS_PER_PUD); - } else { - base_pud = (pud_t *)pgd_page_vaddr(*pgd); - if (base_pud == lm_alias(kasan_early_shadow_pud)) { - base_pud = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE); - memcpy(base_pud, (void *)kasan_early_shadow_pud, - sizeof(pud_t) * PTRS_PER_PUD); - } + if (p4d_none(*p4d)) { + p = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE); + set_p4d(p4d, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE)); } - pudp = base_pud + pud_index(vaddr); + pudp = pud_offset(p4d, vaddr); do { next = pud_addr_end(vaddr, end); @@ -123,37 +98,28 @@ static void __init kasan_populate_pud(pgd_t *pgd, phys_addr = memblock_phys_alloc(PUD_SIZE, PUD_SIZE); if (phys_addr) { set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_KERNEL)); + memset(__va(phys_addr), KASAN_SHADOW_INIT, PUD_SIZE); continue; } } kasan_populate_pmd(pudp, vaddr, next); } while (pudp++, vaddr = next, vaddr != end); - - /* - * Wait for the whole PGD to be populated before setting the PGD in - * the page table, otherwise, if we did set the PGD before populating - * it entirely, memblock could allocate a page at a physical address - * where KASAN is not populated yet and then we'd get a page fault. - */ - set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_pud)), PAGE_TABLE)); } static void __init kasan_populate_p4d(pgd_t *pgd, unsigned long vaddr, unsigned long end) { phys_addr_t phys_addr; - p4d_t *p4dp, *base_p4d; + p4d_t *p4dp, *p; unsigned long next; - base_p4d = (p4d_t *)pgd_page_vaddr(*pgd); - if (base_p4d == lm_alias(kasan_early_shadow_p4d)) { - base_p4d = memblock_alloc(PTRS_PER_PUD * sizeof(p4d_t), PAGE_SIZE); - memcpy(base_p4d, (void *)kasan_early_shadow_p4d, - sizeof(p4d_t) * PTRS_PER_P4D); + if (pgd_none(*pgd)) { + p = memblock_alloc(PTRS_PER_P4D * sizeof(p4d_t), PAGE_SIZE); + set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE)); } - p4dp = base_p4d + p4d_index(vaddr); + p4dp = p4d_offset(pgd, vaddr); do { next = p4d_addr_end(vaddr, end); @@ -162,34 +128,15 @@ static void __init kasan_populate_p4d(pgd_t *pgd, phys_addr = memblock_phys_alloc(P4D_SIZE, P4D_SIZE); if (phys_addr) { set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_KERNEL)); + memset(__va(phys_addr), KASAN_SHADOW_INIT, P4D_SIZE); continue; } } - kasan_populate_pud((pgd_t *)p4dp, vaddr, next); + kasan_populate_pud(p4dp, vaddr, next); } while (p4dp++, vaddr = next, vaddr != end); - - /* - * Wait for the whole P4D to be populated before setting the P4D in - * the page table, otherwise, if we did set the P4D before populating - * it entirely, memblock could allocate a page at a physical address - * where KASAN is not populated yet and then we'd get a page fault. - */ - set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(base_p4d)), PAGE_TABLE)); } -#define kasan_early_shadow_pgd_next (pgtable_l5_enabled ? \ - (uintptr_t)kasan_early_shadow_p4d : \ - (pgtable_l4_enabled ? \ - (uintptr_t)kasan_early_shadow_pud : \ - (uintptr_t)kasan_early_shadow_pmd)) -#define kasan_populate_pgd_next(pgdp, vaddr, next) \ - (pgtable_l5_enabled ? \ - kasan_populate_p4d(pgdp, vaddr, next) : \ - (pgtable_l4_enabled ? \ - kasan_populate_pud(pgdp, vaddr, next) : \ - kasan_populate_pmd((pud_t *)pgdp, vaddr, next))) - static void __init kasan_populate_pgd(pgd_t *pgdp, unsigned long vaddr, unsigned long end) { @@ -199,25 +146,86 @@ static void __init kasan_populate_pgd(pgd_t *pgdp, do { next = pgd_addr_end(vaddr, end); - if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) { - if (pgd_page_vaddr(*pgdp) == - (unsigned long)lm_alias(kasan_early_shadow_pgd_next)) { - /* - * pgdp can't be none since kasan_early_init - * initialized all KASAN shadow region with - * kasan_early_shadow_pud: if this is still the - * case, that means we can try to allocate a - * hugepage as a replacement. - */ - phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE); - if (phys_addr) { - set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL)); - continue; - } + if (pgd_none(*pgdp) && IS_ALIGNED(vaddr, PGDIR_SIZE) && + (next - vaddr) >= PGDIR_SIZE) { + phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE); + if (phys_addr) { + set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL)); + memset(__va(phys_addr), KASAN_SHADOW_INIT, PGDIR_SIZE); + continue; } } - kasan_populate_pgd_next(pgdp, vaddr, next); + kasan_populate_p4d(pgdp, vaddr, next); + } while (pgdp++, vaddr = next, vaddr != end); +} + +static void __init kasan_early_clear_pud(p4d_t *p4dp, + unsigned long vaddr, unsigned long end) +{ + pud_t *pudp, *base_pud; + unsigned long next; + + if (!pgtable_l4_enabled) { + pudp = (pud_t *)p4dp; + } else { + base_pud = pt_ops.get_pud_virt(pfn_to_phys(_p4d_pfn(*p4dp))); + pudp = base_pud + pud_index(vaddr); + } + + do { + next = pud_addr_end(vaddr, end); + + if (IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) { + pud_clear(pudp); + continue; + } + + BUG(); + } while (pudp++, vaddr = next, vaddr != end); +} + +static void __init kasan_early_clear_p4d(pgd_t *pgdp, + unsigned long vaddr, unsigned long end) +{ + p4d_t *p4dp, *base_p4d; + unsigned long next; + + if (!pgtable_l5_enabled) { + p4dp = (p4d_t *)pgdp; + } else { + base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgdp))); + p4dp = base_p4d + p4d_index(vaddr); + } + + do { + next = p4d_addr_end(vaddr, end); + + if (pgtable_l4_enabled && IS_ALIGNED(vaddr, P4D_SIZE) && + (next - vaddr) >= P4D_SIZE) { + p4d_clear(p4dp); + continue; + } + + kasan_early_clear_pud(p4dp, vaddr, next); + } while (p4dp++, vaddr = next, vaddr != end); +} + +static void __init kasan_early_clear_pgd(pgd_t *pgdp, + unsigned long vaddr, unsigned long end) +{ + unsigned long next; + + do { + next = pgd_addr_end(vaddr, end); + + if (pgtable_l5_enabled && IS_ALIGNED(vaddr, PGDIR_SIZE) && + (next - vaddr) >= PGDIR_SIZE) { + pgd_clear(pgdp); + continue; + } + + kasan_early_clear_p4d(pgdp, vaddr, next); } while (pgdp++, vaddr = next, vaddr != end); } @@ -362,117 +370,64 @@ static void __init kasan_populate(void *start, void *end) unsigned long vend = PAGE_ALIGN((unsigned long)end); kasan_populate_pgd(pgd_offset_k(vaddr), vaddr, vend); - - local_flush_tlb_all(); - memset(start, KASAN_SHADOW_INIT, end - start); -} - -static void __init kasan_shallow_populate_pmd(pgd_t *pgdp, - unsigned long vaddr, unsigned long end) -{ - unsigned long next; - pmd_t *pmdp, *base_pmd; - bool is_kasan_pte; - - base_pmd = (pmd_t *)pgd_page_vaddr(*pgdp); - pmdp = base_pmd + pmd_index(vaddr); - - do { - next = pmd_addr_end(vaddr, end); - is_kasan_pte = (pmd_pgtable(*pmdp) == lm_alias(kasan_early_shadow_pte)); - - if (is_kasan_pte) - pmd_clear(pmdp); - } while (pmdp++, vaddr = next, vaddr != end); } -static void __init kasan_shallow_populate_pud(pgd_t *pgdp, +static void __init kasan_shallow_populate_pud(p4d_t *p4d, unsigned long vaddr, unsigned long end) { unsigned long next; - pud_t *pudp, *base_pud; - pmd_t *base_pmd; - bool is_kasan_pmd; - - base_pud = (pud_t *)pgd_page_vaddr(*pgdp); - pudp = base_pud + pud_index(vaddr); + void *p; + pud_t *pud_k = pud_offset(p4d, vaddr); do { next = pud_addr_end(vaddr, end); - is_kasan_pmd = (pud_pgtable(*pudp) == lm_alias(kasan_early_shadow_pmd)); - if (!is_kasan_pmd) - continue; - - base_pmd = memblock_alloc(PAGE_SIZE, PAGE_SIZE); - set_pud(pudp, pfn_pud(PFN_DOWN(__pa(base_pmd)), PAGE_TABLE)); - - if (IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) + if (pud_none(*pud_k)) { + p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + set_pud(pud_k, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE)); continue; + } - memcpy(base_pmd, (void *)kasan_early_shadow_pmd, PAGE_SIZE); - kasan_shallow_populate_pmd((pgd_t *)pudp, vaddr, next); - } while (pudp++, vaddr = next, vaddr != end); + BUG(); + } while (pud_k++, vaddr = next, vaddr != end); } -static void __init kasan_shallow_populate_p4d(pgd_t *pgdp, +static void __init kasan_shallow_populate_p4d(pgd_t *pgd, unsigned long vaddr, unsigned long end) { unsigned long next; - p4d_t *p4dp, *base_p4d; - pud_t *base_pud; - bool is_kasan_pud; - - base_p4d = (p4d_t *)pgd_page_vaddr(*pgdp); - p4dp = base_p4d + p4d_index(vaddr); + void *p; + p4d_t *p4d_k = p4d_offset(pgd, vaddr); do { next = p4d_addr_end(vaddr, end); - is_kasan_pud = (p4d_pgtable(*p4dp) == lm_alias(kasan_early_shadow_pud)); - - if (!is_kasan_pud) - continue; - - base_pud = memblock_alloc(PAGE_SIZE, PAGE_SIZE); - set_p4d(p4dp, pfn_p4d(PFN_DOWN(__pa(base_pud)), PAGE_TABLE)); - if (IS_ALIGNED(vaddr, P4D_SIZE) && (next - vaddr) >= P4D_SIZE) + if (p4d_none(*p4d_k)) { + p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + set_p4d(p4d_k, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE)); continue; + } - memcpy(base_pud, (void *)kasan_early_shadow_pud, PAGE_SIZE); - kasan_shallow_populate_pud((pgd_t *)p4dp, vaddr, next); - } while (p4dp++, vaddr = next, vaddr != end); + kasan_shallow_populate_pud(p4d_k, vaddr, end); + } while (p4d_k++, vaddr = next, vaddr != end); } -#define kasan_shallow_populate_pgd_next(pgdp, vaddr, next) \ - (pgtable_l5_enabled ? \ - kasan_shallow_populate_p4d(pgdp, vaddr, next) : \ - (pgtable_l4_enabled ? \ - kasan_shallow_populate_pud(pgdp, vaddr, next) : \ - kasan_shallow_populate_pmd(pgdp, vaddr, next))) - static void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end) { unsigned long next; void *p; pgd_t *pgd_k = pgd_offset_k(vaddr); - bool is_kasan_pgd_next; do { next = pgd_addr_end(vaddr, end); - is_kasan_pgd_next = (pgd_page_vaddr(*pgd_k) == - (unsigned long)lm_alias(kasan_early_shadow_pgd_next)); - if (is_kasan_pgd_next) { + if (pgd_none(*pgd_k)) { p = memblock_alloc(PAGE_SIZE, PAGE_SIZE); set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE)); - } - - if (IS_ALIGNED(vaddr, PGDIR_SIZE) && (next - vaddr) >= PGDIR_SIZE) continue; + } - memcpy(p, (void *)kasan_early_shadow_pgd_next, PAGE_SIZE); - kasan_shallow_populate_pgd_next(pgd_k, vaddr, next); + kasan_shallow_populate_p4d(pgd_k, vaddr, next); } while (pgd_k++, vaddr = next, vaddr != end); } @@ -482,7 +437,37 @@ static void __init kasan_shallow_populate(void *start, void *end) unsigned long vend = PAGE_ALIGN((unsigned long)end); kasan_shallow_populate_pgd(vaddr, vend); - local_flush_tlb_all(); +} + +static void create_tmp_mapping(void) +{ + void *ptr; + p4d_t *base_p4d; + + /* + * We need to clean the early mapping: this is hard to achieve "in-place", + * so install a temporary mapping like arm64 and x86 do. + */ + memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(pgd_t) * PTRS_PER_PGD); + + /* Copy the last p4d since it is shared with the kernel mapping. */ + if (pgtable_l5_enabled) { + ptr = (p4d_t *)pgd_page_vaddr(*pgd_offset_k(KASAN_SHADOW_END)); + memcpy(tmp_p4d, ptr, sizeof(p4d_t) * PTRS_PER_P4D); + set_pgd(&tmp_pg_dir[pgd_index(KASAN_SHADOW_END)], + pfn_pgd(PFN_DOWN(__pa(tmp_p4d)), PAGE_TABLE)); + base_p4d = tmp_p4d; + } else { + base_p4d = (p4d_t *)tmp_pg_dir; + } + + /* Copy the last pud since it is shared with the kernel mapping. */ + if (pgtable_l4_enabled) { + ptr = (pud_t *)p4d_page_vaddr(*(base_p4d + p4d_index(KASAN_SHADOW_END))); + memcpy(tmp_pud, ptr, sizeof(pud_t) * PTRS_PER_PUD); + set_p4d(&base_p4d[p4d_index(KASAN_SHADOW_END)], + pfn_p4d(PFN_DOWN(__pa(tmp_pud)), PAGE_TABLE)); + } } void __init kasan_init(void) @@ -490,10 +475,27 @@ void __init kasan_init(void) phys_addr_t p_start, p_end; u64 i; - if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) + create_tmp_mapping(); + csr_write(CSR_SATP, PFN_DOWN(__pa(tmp_pg_dir)) | satp_mode); + + kasan_early_clear_pgd(pgd_offset_k(KASAN_SHADOW_START), + KASAN_SHADOW_START, KASAN_SHADOW_END); + + kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)FIXADDR_START), + (void *)kasan_mem_to_shadow((void *)VMALLOC_START)); + + if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) { kasan_shallow_populate( (void *)kasan_mem_to_shadow((void *)VMALLOC_START), (void *)kasan_mem_to_shadow((void *)VMALLOC_END)); + /* Shallow populate modules and BPF which are vmalloc-allocated */ + kasan_shallow_populate( + (void *)kasan_mem_to_shadow((void *)MODULES_VADDR), + (void *)kasan_mem_to_shadow((void *)MODULES_END)); + } else { + kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)VMALLOC_START), + (void *)kasan_mem_to_shadow((void *)VMALLOC_END)); + } /* Populate the linear mapping */ for_each_mem_range(i, &p_start, &p_end) { @@ -506,8 +508,8 @@ void __init kasan_init(void) kasan_populate(kasan_mem_to_shadow(start), kasan_mem_to_shadow(end)); } - /* Populate kernel, BPF, modules mapping */ - kasan_populate(kasan_mem_to_shadow((const void *)MODULES_VADDR), + /* Populate kernel */ + kasan_populate(kasan_mem_to_shadow((const void *)MODULES_END), kasan_mem_to_shadow((const void *)MODULES_VADDR + SZ_2G)); for (i = 0; i < PTRS_PER_PTE; i++) @@ -518,4 +520,7 @@ void __init kasan_init(void) memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE); init_task.kasan_depth = 0; + + csr_write(CSR_SATP, PFN_DOWN(__pa(swapper_pg_dir)) | satp_mode); + local_flush_tlb_all(); }