diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2021-01-10 19:05:08 +0100 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2021-01-26 22:11:38 +0100 |
| commit | 2fcb4090cd7352665ecb756990a3087bfd86a295 (patch) | |
| tree | 4562c5264a7b6326b8cdf82ebe379bc351ab58d4 /arch/um/drivers/ubd_kern.c | |
| parent | f4172b084342fd3f9e38c10650ffe19eac30d8ce (diff) | |
Revert "um: allocate a guard page to helper threads"
This reverts commit ef4459a6da09 ("um: allocate a guard page to
helper threads"), it's broken in multiple ways:
1) the free no longer matches the alloc; and
2) more importantly, the set_memory_ro() causes allocation of
page tables for the normal memory that doesn't have any,
and that later causes corruption and crashes (usually but
not always in vfree()).
We could fix the first bug and use vmalloc() to work around the
second, but set_memory_ro() actually doesn't do anything either
so I'll just revert that as well.
Reported-by: Benjamin Berg <benjamin@sipsolutions.net>
Fixes: ef4459a6da09 ("um: allocate a guard page to helper threads")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/drivers/ubd_kern.c')
| -rw-r--r-- | arch/um/drivers/ubd_kern.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c index bd16b17ba4d6..8e0b43cf089f 100644 --- a/arch/um/drivers/ubd_kern.c +++ b/arch/um/drivers/ubd_kern.c @@ -1241,7 +1241,7 @@ static int __init ubd_driver_init(void){ /* Letting ubd=sync be like using ubd#s= instead of ubd#= is * enough. So use anyway the io thread. */ } - stack = alloc_stack(0); + stack = alloc_stack(0, 0); io_pid = start_io_thread(stack + PAGE_SIZE - sizeof(void *), &thread_fd); if(io_pid < 0){ |