Hi Julien, > -----Original Message----- > Subject: [PATCH 6/7] xen/arm: mm: Add missing ISB in xen_pt_update() > > From: Julien Grall <jgr...@amazon.com> > > Per the Arm Arm, (Armv7 DDI406C.d A3.8.3 and Armv8 DDI 0487J.a B2.3.12): > > "The DMB and DSB memory barriers affect reads and writes to the memory > system generated by load/store instructions and data or unified cache > maintenance operations being executed by the processor. Instruction > fetches or accesses caused by a hardware translation table access are > not explicit accesses." > > Note that second sentence is not part of the newer Armv8 spec. But the > interpretation is not much different. > > The updated entry will not be used until xen_pt_update() completes. > So rather than adding the ISB after write_pte() in create_xen_table() > and xen_pt-update_entry(), add it in xen_pt_update(). > > Also document the reasoning of the deferral after each write_pte() calls. > > Fixes: 07d11f63d03e ("xen/arm: mm: Avoid flushing the TLBs when mapping > are inserted") > Signed-off-by: Julien Grall <jgr...@amazon.com>
Reviewed-by: Henry Wang <henry.w...@arm.com> I've also tested this patch on top of today's staging by our internal CI, and this patch looks good, so: Tested-by: Henry Wang <henry.w...@arm.com> Kind regards, Henry