mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 17:01:14 +00:00
![]() When running following code in a machine which has VIVT caches and USE_SPLIT_PTLOCKS is not defined: fd = open("/etc/passwd", O_RDONLY); addr = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0); addr2 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0); v = *((int *)addr); we will hang in spinlock recursion in the page fault handler: BUG: spinlock recursion on CPU#0, mmap_test/717 lock: c5e295d8, .magic: dead4ead, .owner: mmap_test/717, .owner_cpu: 0 [<c0026604>] (unwind_backtrace+0x0/0xec) [<c014ee48>] (do_raw_spin_lock+0x40/0x140) [<c0027f68>] (update_mmu_cache+0x208/0x250) [<c0079db4>] (__do_fault+0x320/0x3ec) [<c007af7c>] (handle_mm_fault+0x2f0/0x6d8) [<c0027834>] (do_page_fault+0xdc/0x1cc) [<c00202d0>] (do_DataAbort+0x34/0x94) This comes from the fact that when USE_SPLIT_PTLOCKS is not defined, the only lock protecting the page tables is mm->page_table_lock which is already locked before update_mmu_cache() is called. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> |
||
---|---|---|
.. | ||
alpha | ||
arm | ||
avr32 | ||
blackfin | ||
cris | ||
frv | ||
h8300 | ||
ia64 | ||
m32r | ||
m68k | ||
m68knommu | ||
microblaze | ||
mips | ||
mn10300 | ||
parisc | ||
powerpc | ||
s390 | ||
score | ||
sh | ||
sparc | ||
tile | ||
um | ||
x86 | ||
xtensa | ||
.gitignore | ||
Kconfig |