diff options
| author | Alexander Gordeev <agordeev@linux.ibm.com> | 2024-09-30 14:21:19 +0200 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-10-09 12:47:19 -0700 |
| commit | 3d5854d75e3187147613130561b58f0b06166172 (patch) | |
| tree | acaf406a23a546d445a542e2573f6cefaf4154d8 /arch/s390 | |
| parent | 76503e1fa1a53ef041a120825d5ce81c7fe7bdd7 (diff) | |
fs/proc/kcore.c: allow translation of physical memory addresses
When /proc/kcore is read an attempt to read the first two pages results in
HW-specific page swap on s390 and another (so called prefix) pages are
accessed instead. That leads to a wrong read.
Allow architecture-specific translation of memory addresses using
kc_xlate_dev_mem_ptr() and kc_unxlate_dev_mem_ptr() callbacks similarily
to /dev/mem xlate_dev_mem_ptr() and unxlate_dev_mem_ptr() callbacks. That
way an architecture can deal with specific physical memory ranges.
Re-use the existing /dev/mem callback implementation on s390, which
handles the described prefix pages swapping correctly.
For other architectures the default callback is basically NOP. It is
expected the condition (vaddr == __va(__pa(vaddr))) always holds true for
KCORE_RAM memory type.
Link: https://lkml.kernel.org/r/20240930122119.1651546-1-agordeev@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Suggested-by: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/include/asm/io.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/s390/include/asm/io.h b/arch/s390/include/asm/io.h index 0fbc992d7a5e..fc9933a743d6 100644 --- a/arch/s390/include/asm/io.h +++ b/arch/s390/include/asm/io.h @@ -16,8 +16,10 @@ #include <asm/pci_io.h> #define xlate_dev_mem_ptr xlate_dev_mem_ptr +#define kc_xlate_dev_mem_ptr xlate_dev_mem_ptr void *xlate_dev_mem_ptr(phys_addr_t phys); #define unxlate_dev_mem_ptr unxlate_dev_mem_ptr +#define kc_unxlate_dev_mem_ptr unxlate_dev_mem_ptr void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr); #define IO_SPACE_LIMIT 0 |