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/include/asm/book3s/64/radix.h | |
| 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/include/asm/book3s/64/radix.h')
| -rw-r--r-- | arch/powerpc/include/asm/book3s/64/radix.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/book3s/64/radix.h b/arch/powerpc/include/asm/book3s/64/radix.h index 59cab558e2f0..d090d9612348 100644 --- a/arch/powerpc/include/asm/book3s/64/radix.h +++ b/arch/powerpc/include/asm/book3s/64/radix.h @@ -316,5 +316,8 @@ int radix__create_section_mapping(unsigned long start, unsigned long end, int nid, pgprot_t prot); int radix__remove_section_mapping(unsigned long start, unsigned long end); #endif /* CONFIG_MEMORY_HOTPLUG */ + +void radix__kernel_map_pages(struct page *page, int numpages, int enable); + #endif /* __ASSEMBLY__ */ #endif |