diff options
| author |   Alexander Gordeev <agordeev@linux.ibm.com> | 2022-01-21 10:44:25 +0100 |
|---|---|---|
| committer |   Vasily Gorbik <gor@linux.ibm.com> | 2022-02-06 23:31:29 +0100 |
| commit | 1f231e295024d88950c7e4b91f91a47bbeff1637 (patch) | |
| tree | 7d2bd39db09a4869a882a3c8de38cef370c14291 /arch/s390/mm | |
| parent | s390/ftrace: verify opcode before applying patch (diff) | |
| download | linux-dev-1f231e295024d88950c7e4b91f91a47bbeff1637.tar.xz linux-dev-1f231e295024d88950c7e4b91f91a47bbeff1637.zip | |
s390/maccess: fix absolute lowcore virtual vs physical address confusion
Due to historical reasons memcpy_absolute() and friend functions
misuse the notion of physical vs virtual addresses difference.
Note: this does not fix a bug currently, since virtual and physical
addresses are identical.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390/mm')
| -rw-r--r-- | arch/s390/mm/maccess.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/arch/s390/mm/maccess.c b/arch/s390/mm/maccess.c index c1ed1f51c25d..d4d311cb2bb5 100644 --- a/arch/s390/mm/maccess.c +++ b/arch/s390/mm/maccess.c @@ -199,15 +199,15 @@ out: /* * Check if physical address is within prefix or zero page */ -static int is_swapped(unsigned long addr) +static int is_swapped(phys_addr_t addr) { - unsigned long lc; + phys_addr_t lc; int cpu; if (addr < sizeof(struct lowcore)) return 1; for_each_online_cpu(cpu) { - lc = (unsigned long) lowcore_ptr[cpu]; + lc = virt_to_phys(lowcore_ptr[cpu]); if (addr > lc + sizeof(struct lowcore) - 1 || addr < lc) continue; return 1; @@ -223,7 +223,8 @@ static int is_swapped(unsigned long addr) */ void *xlate_dev_mem_ptr(phys_addr_t addr) { - void *bounce = (void *) addr; + void *ptr = phys_to_virt(addr); + void *bounce = ptr; unsigned long size; cpus_read_lock(); @@ -232,7 +233,7 @@ void *xlate_dev_mem_ptr(phys_addr_t addr) size = PAGE_SIZE - (addr & ~PAGE_MASK); bounce = (void *) __get_free_page(GFP_ATOMIC); if (bounce) - memcpy_absolute(bounce, (void *) addr, size); + memcpy_absolute(bounce, ptr, size); } preempt_enable(); cpus_read_unlock(); @@ -242,8 +243,8 @@ void *xlate_dev_mem_ptr(phys_addr_t addr) /* * Free converted buffer for /dev/mem access (if necessary) */ -void unxlate_dev_mem_ptr(phys_addr_t addr, void *buf) +void unxlate_dev_mem_ptr(phys_addr_t addr, void *ptr) { - if ((void *) addr != buf) - free_page((unsigned long) buf); + if (addr != virt_to_phys(ptr)) + free_page((unsigned long)ptr); } |