Le 25/01/2019 à 01:55, Benjamin Herrenschmidt a écrit :
On Thu, 2019-01-24 at 19:48 +0530, Chandan Rajendra wrote:
- Here we execute "LD rB,0,r4". In the case of this bug, r4 has an unaligned
value and hence ends up accessing the "next" double word. The "next" double
word happens to occur after the last page mapped into the kernel's address
space and hence this leads to the previously listed oops.
This is interesting ... should we mark the last page of any piece of
mapped linear mapping as reserved to avoid that sort of issue ?
Or revert to a normal comparison once remaining length is < 8 and r4 in
unaligned ?
Christophe
Nick ? Aneesh ?
Cheers,
Ben.