On 17.04.19 22:55, Sven Schnelle wrote: > On Fri, Apr 12, 2019 at 07:12:04PM -0400, John David Anglin wrote: >> TLB operations only need to be serialized on machines with the Merced (Stretch) bus. >> The only machines in this category are L and N class, and they require a 64-bit PA 2.0 >> kernel. On these machines, we use local TLB purges in the tmpalias routines. We don't >> need to serialize TLB purges on all other machines. Thus, the lock/unlock code can be >> removed when CONFIG_PA20 is not defined. Further, when CONFIG_PA20 is not defined, >> alternative patching converts the TLB purges to local purges when PA 2.0 hardware has >> been detected. >> >> Signed-off-by: John David Anglin <dave.anglin@xxxxxxxx> > > I had this patch running on my C8000 and J5000 for a few days, and haven't > encountered any issues. Nah... I do have one of the critical machines (rp5470), and I tried to add the necessary code to detect and handle the TLB serialization. Until now the patch sadly doesn't work yet (hangs at boot), it still needs more work. You can find it in my git tree: https://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux.git/commit/?h=tlb-flush-merced-bus&id=fc6044f83cb9828ec6ebecb23a46549d9ebc518f Helge
