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Date:   Tue, 22 Feb 2022 21:21:39 -0800
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Subject: [RFC PATCH 03/47] mm: asi: Switch to unrestricted address space when
 entering scheduler
From:   Junaid Shahid <junaids@google.com>
To:     linux-kernel@vger.kernel.org
Cc:     kvm@vger.kernel.org, pbonzini@redhat.com, jmattson@google.com,
        pjt@google.com, oweisse@google.com, alexandre.chartre@oracle.com,
        rppt@linux.ibm.com, dave.hansen@linux.intel.com,
        peterz@infradead.org, tglx@linutronix.de, luto@kernel.org,
        linux-mm@kvack.org
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Precedence: bulk

To keep things simpler, we run the scheduler only in the full
unrestricted address space for the time being.

Signed-off-by: Junaid Shahid <junaids@google.com>


---
 kernel/sched/core.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 77563109c0ea..44ea197c16ea 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -19,6 +19,7 @@
 
 #include <asm/switch_to.h>
 #include <asm/tlb.h>
+#include <asm/asi.h>
 
 #include "../workqueue_internal.h"
 #include "../../fs/io-wq.h"
@@ -6141,6 +6142,10 @@ static void __sched notrace __schedule(unsigned int sched_mode)
 	rq = cpu_rq(cpu);
 	prev = rq->curr;
 
+	/* This could possibly be delayed to just before the context switch. */
+	VM_WARN_ON(!asi_is_target_unrestricted());
+	asi_exit();
+
 	schedule_debug(prev, !!sched_mode);
 
 	if (sched_feat(HRTICK) || sched_feat(HRTICK_DL))
-- 
2.35.1.473.g83b2b277ed-goog