/* getroot.c: get the root dentry for an NFS mount * * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved. * Written by David Howells (dhowells@redhat.com) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "internal.h" #define NFSDBG_FACILITY NFSDBG_CLIENT /* * Set the superblock root dentry. * Note that this function frees the inode in case of error. */ static int nfs_superblock_set_dummy_root(struct super_block *sb, struct inode *inode) { /* The mntroot acts as the dummy root dentry for this superblock */ if (sb->s_root == NULL) { sb->s_root = d_make_root(inode); if (sb->s_root == NULL) return -ENOMEM; ihold(inode); /* * Ensure that this dentry is invisible to d_find_alias(). * Otherwise, it may be spliced into the tree by * d_splice_alias if a parent directory from the same * filesystem gets mounted at a later time. * This again causes shrink_dcache_for_umount_subtree() to * Oops, since the test for IS_ROOT() will fail. */ spin_lock(&d_inode(sb->s_root)->i_lock); spin_lock(&sb->s_root->d_lock); hlist_del_init(&sb->s_root->d_u.d_alias); spin_unlock(&sb->s_root->d_lock); spin_unlock(&d_inode(sb->s_root)->i_lock); } return 0; } /* * get an NFS2/NFS3 root dentry from the root filehandle */ struct dentry *nfs_get_root(struct super_block *sb, struct nfs_fh *mntfh, const char *devname) { struct nfs_server *server = NFS_SB(sb); struct nfs_fsinfo fsinfo; struct dentry *ret; struct inode *inode; void *name = kstrdup(devname, GFP_KERNEL); int error; if (!name) return ERR_PTR(-ENOMEM); /* get the actual root for this mount */ fsinfo.fattr = nfs_alloc_fattr(); if (fsinfo.fattr == NULL) { kfree(name); return ERR_PTR(-ENOMEM); } error = server->nfs_client->rpc_ops->getroot(server, mntfh, &fsinfo); if (error < 0) { dprintk("nfs_get_root: getattr error = %d\n", -error); ret = ERR_PTR(error); goto out; } inode = nfs_fhget(sb, mntfh, fsinfo.fattr, NULL); if (IS_ERR(inode)) { dprintk("nfs_get_root: get root inode failed\n"); ret = ERR_CAST(inode); goto out; } error = nfs_superblock_set_dummy_root(sb, inode); if (error != 0) { ret = ERR_PTR(error); goto out; } /* root dentries normally start off anonymous and get spliced in later * if the dentry tree reaches them; however if the dentry already * exists, we'll pick it up at this point and use it as the root */ ret = d_obtain_root(inode); if (IS_ERR(ret)) { dprintk("nfs_get_root: get root dentry failed\n"); goto out; } security_d_instantiate(ret, inode); spin_lock(&ret->d_lock); if (IS_ROOT(ret) && !ret->d_fsdata && !(ret->d_flags & DCACHE_NFSFS_RENAMED)) { ret->d_fsdata = name; name = NULL; } spin_unlock(&ret->d_lock); out: kfree(name); nfs_free_fattr(fsinfo.fattr); return ret; } ions
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authorBorislav Petkov <bp@suse.de>2017-01-20 21:29:40 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-23 09:39:55 +0100
commitc26665ab5c49ad3e142e0f054ca3204f259ba09c (patch)
tree3bab11918e18e9d25ef7544dba05cdf39d1abec5 /tools/testing/selftests
parent7a308bb3016f57e5be11a677d15b821536419d36 (diff)
x86/microcode/intel: Drop stashed AP patch pointer optimization
This was meant to save us the scanning of the microcode containter in the initrd since the first AP had already done that but it can also hurt us: Imagine a single hyperthreaded CPU (Intel(R) Atom(TM) CPU N270, for example) which updates the microcode on the BSP but since the microcode engine is shared between the two threads, the update on CPU1 doesn't happen because it has already happened on CPU0 and we don't find a newer microcode revision on CPU1. Which doesn't set the intel_ucode_patch pointer and at initrd jettisoning time we don't save the microcode patch for later application. Now, when we suspend to RAM, the loaded microcode gets cleared so we need to reload but there's no patch saved in the cache. Removing the optimization fixes this issue and all is fine and dandy. Fixes: 06b8534cb728 ("x86/microcode: Rework microcode loading") Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20170120202955.4091-2-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'tools/testing/selftests')