From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration 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 Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- include/asm-generic/seccomp.h | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 include/asm-generic/seccomp.h (limited to 'include/asm-generic/seccomp.h') diff --git a/include/asm-generic/seccomp.h b/include/asm-generic/seccomp.h new file mode 100644 index 000000000..6b6f42bc5 --- /dev/null +++ b/include/asm-generic/seccomp.h @@ -0,0 +1,43 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * include/asm-generic/seccomp.h + * + * Copyright (C) 2014 Linaro Limited + * Author: AKASHI Takahiro + */ +#ifndef _ASM_GENERIC_SECCOMP_H +#define _ASM_GENERIC_SECCOMP_H + +#include + +#if defined(CONFIG_COMPAT) && !defined(__NR_seccomp_read_32) +#define __NR_seccomp_read_32 __NR_read +#define __NR_seccomp_write_32 __NR_write +#define __NR_seccomp_exit_32 __NR_exit +#ifndef __NR_seccomp_sigreturn_32 +#define __NR_seccomp_sigreturn_32 __NR_rt_sigreturn +#endif +#endif /* CONFIG_COMPAT && ! already defined */ + +#define __NR_seccomp_read __NR_read +#define __NR_seccomp_write __NR_write +#define __NR_seccomp_exit __NR_exit +#ifndef __NR_seccomp_sigreturn +#define __NR_seccomp_sigreturn __NR_rt_sigreturn +#endif + +#ifdef CONFIG_COMPAT +#ifndef get_compat_mode1_syscalls +static inline const int *get_compat_mode1_syscalls(void) +{ + static const int mode1_syscalls_32[] = { + __NR_seccomp_read_32, __NR_seccomp_write_32, + __NR_seccomp_exit_32, __NR_seccomp_sigreturn_32, + -1, /* negative terminated */ + }; + return mode1_syscalls_32; +} +#endif +#endif /* CONFIG_COMPAT */ + +#endif /* _ASM_GENERIC_SECCOMP_H */ -- cgit v1.3.1