diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2020-11-16 11:32:53 -0800 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2020-11-16 21:19:24 +0100 |
| commit | 1eb0616c2df5b78c301eaa7bd2ee859f43915001 (patch) | |
| tree | 402ec6ffc60b8f0e24495b78684704a4c3eeb19b /arch/xtensa/mm/mmu.c | |
| parent | 2a656cad337e0e1ca582f58847d7b0c7eeba4dc8 (diff) | |
xtensa/mm/highmem: Make generic kmap_atomic() work correctly
The conversion to the generic kmap_atomic() implementation missed the fact
that xtensa's fixmap works bottom up while all other implementations work
top down. There is no real reason why xtensa needs to work that way.
Cure it by:
- Using the generic fix_to_virt()/virt_to_fix() functions which work top
down
- Adjusting the mapping defines
- Using the generic index calculation for the non cache aliasing case
- Making the cache colour offset reverse so the effective index is correct
While at it, remove the outdated and misleading comment above the fixmap
enum which originates from the initial copy&pasta of this code from i386.
[ Max: Fixed the off by one in the index calculation ]
Fixes: 629ed3f7dad2 ("xtensa/mm/highmem: Switch to generic kmap atomic")
Reported-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/r/20201116193253.23875-1-jcmvbkbc@gmail.com
Diffstat (limited to 'arch/xtensa/mm/mmu.c')
| -rw-r--r-- | arch/xtensa/mm/mmu.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c index fd2193df8a14..7e4d97dc8bd8 100644 --- a/arch/xtensa/mm/mmu.c +++ b/arch/xtensa/mm/mmu.c @@ -52,7 +52,8 @@ static void * __init init_pmd(unsigned long vaddr, unsigned long n_pages) static void __init fixedrange_init(void) { - init_pmd(__fix_to_virt(0), __end_of_fixed_addresses); + BUILD_BUG_ON(FIXADDR_START < TLBTEMP_BASE_1 + TLBTEMP_SIZE); + init_pmd(FIXADDR_START, __end_of_fixed_addresses); } #endif |