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 --- scripts/dtc/srcpos.h | 104 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 scripts/dtc/srcpos.h (limited to 'scripts/dtc/srcpos.h') diff --git a/scripts/dtc/srcpos.h b/scripts/dtc/srcpos.h new file mode 100644 index 000000000..4d60b50e3 --- /dev/null +++ b/scripts/dtc/srcpos.h @@ -0,0 +1,104 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright 2007 Jon Loeliger, Freescale Semiconductor, Inc. + */ + +#ifndef SRCPOS_H +#define SRCPOS_H + +#include +#include +#include "util.h" + +struct srcfile_state { + FILE *f; + char *name; + char *dir; + int lineno, colno; + struct srcfile_state *prev; +}; + +extern FILE *depfile; /* = NULL */ +extern struct srcfile_state *current_srcfile; /* = NULL */ + +/** + * Open a source file. + * + * If the source file is a relative pathname, then it is searched for in the + * current directory (the directory of the last source file read) and after + * that in the search path. + * + * We work through the search path in order from the first path specified to + * the last. + * + * If the file is not found, then this function does not return, but calls + * die(). + * + * @param fname Filename to search + * @param fullnamep If non-NULL, it is set to the allocated filename of the + * file that was opened. The caller is then responsible + * for freeing the pointer. + * @return pointer to opened FILE + */ +FILE *srcfile_relative_open(const char *fname, char **fullnamep); + +void srcfile_push(const char *fname); +bool srcfile_pop(void); + +/** + * Add a new directory to the search path for input files + * + * The new path is added at the end of the list. + * + * @param dirname Directory to add + */ +void srcfile_add_search_path(const char *dirname); + +struct srcpos { + int first_line; + int first_column; + int last_line; + int last_column; + struct srcfile_state *file; + struct srcpos *next; +}; + +#define YYLTYPE struct srcpos + +#define YYLLOC_DEFAULT(Current, Rhs, N) \ + do { \ + if (N) { \ + (Current).first_line = YYRHSLOC(Rhs, 1).first_line; \ + (Current).first_column = YYRHSLOC(Rhs, 1).first_column; \ + (Current).last_line = YYRHSLOC(Rhs, N).last_line; \ + (Current).last_column = YYRHSLOC (Rhs, N).last_column; \ + (Current).file = YYRHSLOC(Rhs, N).file; \ + } else { \ + (Current).first_line = (Current).last_line = \ + YYRHSLOC(Rhs, 0).last_line; \ + (Current).first_column = (Current).last_column = \ + YYRHSLOC(Rhs, 0).last_column; \ + (Current).file = YYRHSLOC (Rhs, 0).file; \ + } \ + (Current).next = NULL; \ + } while (0) + + +extern void srcpos_update(struct srcpos *pos, const char *text, int len); +extern struct srcpos *srcpos_copy(struct srcpos *pos); +extern struct srcpos *srcpos_extend(struct srcpos *new_srcpos, + struct srcpos *old_srcpos); +extern void srcpos_free(struct srcpos *pos); +extern char *srcpos_string(struct srcpos *pos); +extern char *srcpos_string_first(struct srcpos *pos, int level); +extern char *srcpos_string_last(struct srcpos *pos, int level); + + +extern void PRINTF(3, 0) srcpos_verror(struct srcpos *pos, const char *prefix, + const char *fmt, va_list va); +extern void PRINTF(3, 4) srcpos_error(struct srcpos *pos, const char *prefix, + const char *fmt, ...); + +extern void srcpos_set_line(char *f, int l); + +#endif /* SRCPOS_H */ -- cgit v1.3.1