summaryrefslogtreecommitdiffstats
path: root/lib/vdso/Makefile.include
diff options
context:
space:
mode:
authorSean Christopherson <seanjc@google.com>2026-09-23 09:37:21 -0700
committerPaolo Bonzini <pbonzini@redhat.com>2026-09-26 00:39:55 -0400
commit93de2a6a4b91b72607136dd656edf03fb399d27f (patch)
tree9220c76eb23cb39a146fac9692ee69afa4aa3135 /lib/vdso/Makefile.include
downloadlinux-stable-93de2a6a4b91b72607136dd656edf03fb399d27f.tar.gz
linux-stable-93de2a6a4b91b72607136dd656edf03fb399d27f.zip
KVM: SEV: Do cache maintenance on the source VM during intra-host migrationgrafted
Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu <fane@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'lib/vdso/Makefile.include')
-rw-r--r--lib/vdso/Makefile.include18
1 files changed, 18 insertions, 0 deletions
diff --git a/lib/vdso/Makefile.include b/lib/vdso/Makefile.include
new file mode 100644
index 000000000..cedbf15f8
--- /dev/null
+++ b/lib/vdso/Makefile.include
@@ -0,0 +1,18 @@
+# SPDX-License-Identifier: GPL-2.0
+
+GENERIC_VDSO_MK_PATH := $(abspath $(lastword $(MAKEFILE_LIST)))
+GENERIC_VDSO_DIR := $(dir $(GENERIC_VDSO_MK_PATH))
+
+c-gettimeofday-$(CONFIG_GENERIC_GETTIMEOFDAY) := $(addprefix $(GENERIC_VDSO_DIR), gettimeofday.c)
+c-getrandom-$(CONFIG_VDSO_GETRANDOM) := $(addprefix $(GENERIC_VDSO_DIR), getrandom.c)
+
+# This cmd checks that the vdso library does not contain dynamic relocations.
+# It has to be called after the linking of the vdso library and requires it
+# as a parameter.
+#
+# As a workaround for some GNU ld ports which produce unneeded R_*_NONE
+# dynamic relocations, ignore R_*_NONE.
+quiet_cmd_vdso_check = VDSOCHK $@
+ cmd_vdso_check = if $(READELF) -rW $@ | grep -v _NONE | grep -q " R_\w*_"; \
+ then (echo >&2 "$@: dynamic relocations are not supported"; \
+ rm -f $@; /bin/false); fi