On Fri, Dec 13, 2019 at 7:23 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote: > > On Dec 13, 2019, at 11:40 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > > > > On Fri, Dec 13, 2019 at 5:26 PM Chuck Lever <chuck.lever@xxxxxxxxxx> wrote: > >>> On Dec 13, 2019, at 9:10 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote: > > > >>> diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c > >>> index 24534db87e86..508d7c6c00b5 100644 > > > > With the old code, dividing by 10 was always fast as > > nn->nfsd4_lease was the size of an integer register. Now it > > is 64 bit wide, and I check that truncating it to 32 bit again > > is safe. > > OK. That comment should state this reason rather than just repeating > what the code does. ;-) I changed the comment now to: + /* + * nfsd4_lease is set to at most one hour in __nfsd4_write_time, + * so we can use 32-bit math on it. Warn if that assumption + * ever stops being true. + */ Modified branch pushed to git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git y2038-nfsd-v2 Arnd