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 --- fs/jfs/jfs_debug.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 fs/jfs/jfs_debug.c (limited to 'fs/jfs/jfs_debug.c') diff --git a/fs/jfs/jfs_debug.c b/fs/jfs/jfs_debug.c new file mode 100644 index 000000000..44b62b3c3 --- /dev/null +++ b/fs/jfs/jfs_debug.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) International Business Machines Corp., 2000-2004 + * Portions Copyright (C) Christoph Hellwig, 2001-2002 + */ + +#include +#include +#include +#include +#include +#include +#include "jfs_incore.h" +#include "jfs_filsys.h" +#include "jfs_debug.h" + +#ifdef PROC_FS_JFS /* see jfs_debug.h */ + +#ifdef CONFIG_JFS_DEBUG +static int jfs_loglevel_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "%d\n", jfsloglevel); + return 0; +} + +static int jfs_loglevel_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, jfs_loglevel_proc_show, NULL); +} + +static ssize_t jfs_loglevel_proc_write(struct file *file, + const char __user *buffer, size_t count, loff_t *ppos) +{ + char c; + + if (get_user(c, buffer)) + return -EFAULT; + + /* yes, I know this is an ASCIIism. --hch */ + if (c < '0' || c > '9') + return -EINVAL; + jfsloglevel = c - '0'; + return count; +} + +static const struct proc_ops jfs_loglevel_proc_ops = { + .proc_open = jfs_loglevel_proc_open, + .proc_read = seq_read, + .proc_lseek = seq_lseek, + .proc_release = single_release, + .proc_write = jfs_loglevel_proc_write, +}; +#endif + +void jfs_proc_init(void) +{ + struct proc_dir_entry *base; + + base = proc_mkdir("fs/jfs", NULL); + if (!base) + return; + +#ifdef CONFIG_JFS_STATISTICS + proc_create_single("lmstats", 0, base, jfs_lmstats_proc_show); + proc_create_single("txstats", 0, base, jfs_txstats_proc_show); + proc_create_single("xtstat", 0, base, jfs_xtstat_proc_show); + proc_create_single("mpstat", 0, base, jfs_mpstat_proc_show); +#endif +#ifdef CONFIG_JFS_DEBUG + proc_create_single("TxAnchor", 0, base, jfs_txanchor_proc_show); + proc_create("loglevel", 0, base, &jfs_loglevel_proc_ops); +#endif +} + +void jfs_proc_clean(void) +{ + remove_proc_subtree("fs/jfs", NULL); +} + +#endif /* PROC_FS_JFS */ -- cgit v1.3.1