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charset="UTF-8" X-Rspamd-Queue-Id: 72272180442C0 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Aug 27, 2020 at 12:38 PM Catalin Marinas wrote: > > On Fri, Aug 14, 2020 at 07:27:06PM +0200, Andrey Konovalov wrote: > > @@ -957,6 +984,7 @@ SYM_FUNC_START(cpu_switch_to) > > mov sp, x9 > > msr sp_el0, x1 > > ptrauth_keys_install_kernel x1, x8, x9, x10 > > + mte_restore_gcr 1, x1, x8, x9 > > scs_save x0, x8 > > scs_load x1, x8 > > ret > > Since we set GCR_EL1 on exception entry and return, why is this needed? > We don't have a per-kernel thread GCR_EL1, it's global to all threads, > so I think cpu_switch_to() should not be touched. Dropping this line from the diff leads to many false-positives... I'll leave this to Vincenzo.