diff options
| author | Will Deacon <will.deacon@arm.com> | 2016-01-05 15:36:59 +0000 |
|---|---|---|
| committer | Jeff Vander Stoep <jeffv@google.com> | 2016-09-18 14:16:37 -0700 |
| commit | 606d0cab2091ee86fa8dc7c77a53a9e59e9fac05 (patch) | |
| tree | 2c6b0f9d40b6f403e701a8f99bedb1621c003287 | |
| parent | cc68289965af2e593fdf5161f7e6407d48d79191 (diff) | |
UPSTREAM: arm64: mm: move pgd_cache initialisation to pgtable_cache_init
Initialising the suppport for EFI runtime services requires us to
allocate a pgd off the back of an early_initcall. On systems where the
PGD_SIZE is smaller than PAGE_SIZE (e.g. 64k pages and 48-bit VA), the
pgd_cache isn't initialised at this stage, and we panic with a NULL
dereference during boot:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
__create_mapping.isra.5+0x84/0x350
create_pgd_mapping+0x20/0x28
efi_create_mapping+0x5c/0x6c
arm_enable_runtime_services+0x154/0x1e4
do_one_initcall+0x8c/0x190
kernel_init_freeable+0x84/0x1ec
kernel_init+0x10/0xe0
ret_from_fork+0x10/0x50
This patch fixes the problem by initialising the pgd_cache earlier, in
the pgtable_cache_init callback, which sounds suspiciously like what it
was intended for.
Reported-by: Dennis Chen <dennis.chen@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Bug: 30369029
Patchset: rework-pagetable
(cherry picked from commit 39b5be9b4233a9f212b98242bddf008f379b5122)
Signed-off-by: Jeff Vander Stoep <jeffv@google.com>
Change-Id: I124f03d19299be93124af35641294bf73c13bb22
| -rw-r--r-- | arch/arm64/include/asm/pgtable.h | 3 | ||||
| -rw-r--r-- | arch/arm64/mm/pgd.c | 12 |
2 files changed, 8 insertions, 7 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 51f382b7e5c7..69d2e2f86bce 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -680,7 +680,8 @@ extern int kern_addr_valid(unsigned long addr); #include <asm-generic/pgtable.h> -#define pgtable_cache_init() do { } while (0) +void pgd_cache_init(void); +#define pgtable_cache_init pgd_cache_init /* * On AArch64, the cache coherency is handled via the set_pte_at() function. diff --git a/arch/arm64/mm/pgd.c b/arch/arm64/mm/pgd.c index cb3ba1b812e7..ae11d4e03d0e 100644 --- a/arch/arm64/mm/pgd.c +++ b/arch/arm64/mm/pgd.c @@ -46,14 +46,14 @@ void pgd_free(struct mm_struct *mm, pgd_t *pgd) kmem_cache_free(pgd_cache, pgd); } -static int __init pgd_cache_init(void) +void __init pgd_cache_init(void) { + if (PGD_SIZE == PAGE_SIZE) + return; + /* * Naturally aligned pgds required by the architecture. */ - if (PGD_SIZE != PAGE_SIZE) - pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE, - SLAB_PANIC, NULL); - return 0; + pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE, + SLAB_PANIC, NULL); } -core_initcall(pgd_cache_init); |