lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 8 Feb 2022 20:29:56 +0200 From: Mike Rapoport <rppt@...nel.org> To: Chao Peng <chao.p.peng@...ux.intel.com> Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, linux-mm@...ck.org, linux-fsdevel@...r.kernel.org, qemu-devel@...gnu.org, Paolo Bonzini <pbonzini@...hat.com>, Jonathan Corbet <corbet@....net>, Sean Christopherson <seanjc@...gle.com>, Vitaly Kuznetsov <vkuznets@...hat.com>, Wanpeng Li <wanpengli@...cent.com>, Jim Mattson <jmattson@...gle.com>, Joerg Roedel <joro@...tes.org>, Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>, x86@...nel.org, "H . Peter Anvin" <hpa@...or.com>, Hugh Dickins <hughd@...gle.com>, Jeff Layton <jlayton@...nel.org>, "J . Bruce Fields" <bfields@...ldses.org>, Andrew Morton <akpm@...ux-foundation.org>, Yu Zhang <yu.c.zhang@...ux.intel.com>, "Kirill A . Shutemov" <kirill.shutemov@...ux.intel.com>, luto@...nel.org, jun.nakajima@...el.com, dave.hansen@...el.com, ak@...ux.intel.com, david@...hat.com Subject: Re: [PATCH v4 04/12] mm/shmem: Support memfile_notifier Hi, On Tue, Jan 18, 2022 at 09:21:13PM +0800, Chao Peng wrote: > It maintains a memfile_notifier list in shmem_inode_info structure and > implements memfile_pfn_ops callbacks defined by memfile_notifier. It > then exposes them to memfile_notifier via > shmem_get_memfile_notifier_info. > > We use SGP_NOALLOC in shmem_get_lock_pfn since the pages should be > allocated by userspace for private memory. If there is no pages > allocated at the offset then error should be returned so KVM knows that > the memory is not private memory. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com> > Signed-off-by: Chao Peng <chao.p.peng@...ux.intel.com> > --- > include/linux/shmem_fs.h | 4 ++ > mm/memfile_notifier.c | 12 +++++- > mm/shmem.c | 81 ++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 96 insertions(+), 1 deletion(-) > > diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h > index 166158b6e917..461633587eaf 100644 > --- a/include/linux/shmem_fs.h > +++ b/include/linux/shmem_fs.h > @@ -9,6 +9,7 @@ > #include <linux/percpu_counter.h> > #include <linux/xattr.h> > #include <linux/fs_parser.h> > +#include <linux/memfile_notifier.h> > > /* inode in-kernel data */ > > @@ -24,6 +25,9 @@ struct shmem_inode_info { > struct shared_policy policy; /* NUMA memory alloc policy */ > struct simple_xattrs xattrs; /* list of xattrs */ > atomic_t stop_eviction; /* hold when working on inode */ > +#ifdef CONFIG_MEMFILE_NOTIFIER > + struct memfile_notifier_list memfile_notifiers; > +#endif > struct inode vfs_inode; > }; > > diff --git a/mm/memfile_notifier.c b/mm/memfile_notifier.c > index 8171d4601a04..b4699cbf629e 100644 > --- a/mm/memfile_notifier.c > +++ b/mm/memfile_notifier.c > @@ -41,11 +41,21 @@ void memfile_notifier_fallocate(struct memfile_notifier_list *list, > srcu_read_unlock(&srcu, id); > } > > +#ifdef CONFIG_SHMEM > +extern int shmem_get_memfile_notifier_info(struct inode *inode, > + struct memfile_notifier_list **list, > + struct memfile_pfn_ops **ops); > +#endif > + > static int memfile_get_notifier_info(struct inode *inode, > struct memfile_notifier_list **list, > struct memfile_pfn_ops **ops) > { > - return -EOPNOTSUPP; > + int ret = -EOPNOTSUPP; > +#ifdef CONFIG_SHMEM > + ret = shmem_get_memfile_notifier_info(inode, list, ops); > +#endif This looks backwards. Can we have some register method for memory backing store and call it from shmem.c? > + return ret; > } > > int memfile_register_notifier(struct inode *inode, -- Sincerely yours, Mike.
Powered by blists - more mailing lists