diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-11-24 11:10:51 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-11-24 11:10:51 -0800 |
| commit | b11266ac91f2d0afc154cdcfc7d7d58fd393fc4a (patch) | |
| tree | 9d92abb11bed1b1eef4ae5a842edbf881890fc06 /arch/arm/mm | |
| parent | 3bfd8fcab548659e3a77000b2302c62a47ab2824 (diff) | |
| parent | 340a982825f76f1cff0daa605970fe47321b5ee7 (diff) | |
Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM fixes from Russell King:
"Two fixes for 6.1:
- fix stacktraces for tracepoint events in Thumb2 mode
- fix for noMMU ZERO_PAGE() implementation"
* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 9266/1: mm: fix no-MMU ZERO_PAGE() implementation
ARM: 9251/1: perf: Fix stacktraces for tracepoint events in THUMB2 kernels
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/nommu.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c index c42debaded95..c1494a4dee25 100644 --- a/arch/arm/mm/nommu.c +++ b/arch/arm/mm/nommu.c @@ -26,6 +26,13 @@ unsigned long vectors_base; +/* + * empty_zero_page is a special page that is used for + * zero-initialized data and COW. + */ +struct page *empty_zero_page; +EXPORT_SYMBOL(empty_zero_page); + #ifdef CONFIG_ARM_MPU struct mpu_rgn_info mpu_rgn_info; #endif @@ -148,9 +155,21 @@ void __init adjust_lowmem_bounds(void) */ void __init paging_init(const struct machine_desc *mdesc) { + void *zero_page; + early_trap_init((void *)vectors_base); mpu_setup(); + + /* allocate the zero page. */ + zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE); + if (!zero_page) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", + __func__, PAGE_SIZE, PAGE_SIZE); + bootmem_init(); + + empty_zero_page = virt_to_page(zero_page); + flush_dcache_page(empty_zero_page); } /* |