diff options
author | Joel Stanley <joel@jms.id.au> | 2021-10-14 08:04:38 +1030 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-10-22 15:22:02 +1100 |
commit | 4f703e7faa67a116016c4678fc88b507c12670c9 (patch) | |
tree | 29b21d3ba6945f30efd81ef52076fc1708774ba4 /arch/powerpc/mm/book3s64/hash_utils.c | |
parent | 3091f5fc5f1df7741ddf326561384e0997eca2a1 (diff) |
powerpc/s64: Clarify that radix lacks DEBUG_PAGEALLOC
The page_alloc.c code will call into __kernel_map_pages() when
DEBUG_PAGEALLOC is configured and enabled.
As the implementation assumes hash, this should crash spectacularly if
not for a bit of luck in __kernel_map_pages(). In this function
linear_map_hash_count is always zero, the for loop exits without doing
any damage.
There are no other platforms that determine if they support
debug_pagealloc at runtime. Instead of adding code to mm/page_alloc.c to
do that, this change turns the map/unmap into a noop when in radix
mode and prints a warning once.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Reformat if per Christophe's suggestion]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211013213438.675095-1-joel@jms.id.au
Diffstat (limited to 'arch/powerpc/mm/book3s64/hash_utils.c')
-rw-r--r-- | arch/powerpc/mm/book3s64/hash_utils.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c index c145776d3ae5..cfd45245d009 100644 --- a/arch/powerpc/mm/book3s64/hash_utils.c +++ b/arch/powerpc/mm/book3s64/hash_utils.c @@ -1988,7 +1988,7 @@ static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi) mmu_kernel_ssize, 0); } -void __kernel_map_pages(struct page *page, int numpages, int enable) +void hash__kernel_map_pages(struct page *page, int numpages, int enable) { unsigned long flags, vaddr, lmi; int i; |