arm64: hibernate: Clean the __hyp_text to PoC after resume

BugLink: https://bugs.launchpad.net/bugs/1837664
commit f7daa9c8fd191724b9ab9580a7be55cd1a67d799 upstream.

During resume hibernate restores all physical memory. Any memory
that is accessed with the MMU disabled needs to be cleaned to the
PoC.

KVMs __hyp_text was previously ommitted as it runs with the MMU
enabled, but now that the hyp-stub is located in this section,
we must clean __hyp_text too.

This ensures secondary CPUs that come online after hibernate
has finished resuming, and load KVM via the freshly written
hyp-stub see the correct instructions.

Signed-off-by: James Morse <james.morse@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index f76c02f28ae5c5f1597932429b51536cc062f0e3..c90092aeb40009621db4af1c113bf26a7cc4e46c 100644 (file)
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -300,8 +300,10 @@ int swsusp_arch_suspend(void)
                dcache_clean_range(__idmap_text_start, __idmap_text_end);
 
                /* Clean kvm setup code to PoC? */
-               if (el2_reset_needed())
+               if (el2_reset_needed()) {
                        dcache_clean_range(__hyp_idmap_text_start, __hyp_idmap_text_end);
+                       dcache_clean_range(__hyp_text_start, __hyp_text_end);
+               }
 
                /* make the crash dump kernel image protected again */
                crash_post_resume();