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[PATCH 04/15] alpha: wire up io_pgetevents system call

by Arnd Bergmann

The io_pgetevents system call was added in linux-4.18 but has no entry for alpha: warning: #warning syscall io_pgetevents not implemented [-Wcpp] Assign a the next system call number here. Cc: stable(a)vger.kernel.org Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> --- arch/alpha/kernel/syscalls/syscall.tbl | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 7b56a53be5e3..e09558edae73 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -451,3 +451,4 @@ 520 common preadv2 sys_preadv2 521 common pwritev2 sys_pwritev2 522 common statx sys_statx +523 common io_pgetevents sys_io_pgetevents -- 2.20.0

6 years, 8 months

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Cross-compiling libbpf from Linux 4.14 tree

by Ignat Korchagin

Good day, We have started to compile libbpf as part of our Linux compilation build plan, however libbpf fails to cross-compile for arm64 on Linux 4.14, but succeeds on Linux 4.19 tree. We compile libbpf with the following command: make -C <whatever>/linux-4.14.91/tools/lib/bpf ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- install And get the below output on 4.14 tree: Auto-detecting system features: ... libelf: [ on ] ... bpf: [ on ] CC /cfsetup_build/build/arm64/libbpf/libbpf.o CC /cfsetup_build/build/arm64/libbpf/bpf.o LD /cfsetup_build/build/arm64/libbpf/libbpf-in.o ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) ld: /cfsetup_build/build/arm64/libbpf/libbpf.o: Relocations in generic ELF (EM: 183) /cfsetup_build/build/arm64/libbpf/libbpf.o: error adding symbols: File in wrong format /cfsetup_build/build/linux-4.14.91/tools/build/Makefile.build:144: recipe for target '/cfsetup_build/build/arm64/libbpf/libbpf-in.o' failed make[2]: *** [/cfsetup_build/build/arm64/libbpf/libbpf-in.o] Error 1 Makefile:158: recipe for target '/cfsetup_build/build/arm64/libbpf/libbpf-in.o' failed make[1]: *** [/cfsetup_build/build/arm64/libbpf/libbpf-in.o] Error 2 Backporting the following commit fixed the build: 7ed1c1901fe52e6c5828deb155920b44b0adabb1: tools: fix cross-compile var clobbering Can we have it officially applied to the Linux 4.14 tree, please? Regards, Ignat

6 years, 8 months

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FAILED: patch "[PATCH] sunrpc: use-after-free in svc_process_common()" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d4b09acf924b84bae77cad090a9d108e70b43643 Mon Sep 17 00:00:00 2001 From: Vasily Averin <vvs(a)virtuozzo.com> Date: Mon, 24 Dec 2018 14:44:52 +0300 Subject: [PATCH] sunrpc: use-after-free in svc_process_common() if node have NFSv41+ mounts inside several net namespaces it can lead to use-after-free in svc_process_common() svc_process_common() /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE svc_process_common() can use incorrect rqstp->rq_xprt, its caller function bc_svc_process() takes it from serv->sv_bc_xprt. The problem is that serv is global structure but sv_bc_xprt is assigned per-netnamespace. According to Trond, the whole "let's set up rqstp->rq_xprt for the back channel" is nothing but a giant hack in order to work around the fact that svc_process_common() uses it to find the xpt_ops, and perform a couple of (meaningless for the back channel) tests of xpt_flags. All we really need in svc_process_common() is to be able to run rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr() Bruce J Fields points that this xpo_prep_reply_hdr() call is an awfully roundabout way just to do "svc_putnl(resv, 0);" in the tcp case. This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(), now it calls svc_process_common() with rqstp->rq_xprt = NULL. To adjust reply header svc_process_common() just check rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case. To handle rqstp->rq_xprt = NULL case in functions called from svc_process_common() patch intruduces net namespace pointer svc_rqst->rq_bc_net and adjust SVC_NET() definition. Some other function was also adopted to properly handle described case. Signed-off-by: Vasily Averin <vvs(a)virtuozzo.com> Cc: stable(a)vger.kernel.org Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup") Signed-off-by: J. Bruce Fields <bfields(a)redhat.com> diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 73e130a840ce..fdb6b317d974 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -295,9 +295,12 @@ struct svc_rqst { struct svc_cacherep * rq_cacherep; /* cache info */ struct task_struct *rq_task; /* service thread */ spinlock_t rq_lock; /* per-request lock */ + struct net *rq_bc_net; /* pointer to backchannel's + * net namespace + */ }; -#define SVC_NET(svc_rqst) (svc_rqst->rq_xprt->xpt_net) +#define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) /* * Rigorous type checking on sockaddr type conversions diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index 28e384186c35..8617f4fd6b70 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -569,7 +569,8 @@ TRACE_EVENT(svc_process, __field(u32, vers) __field(u32, proc) __string(service, name) - __string(addr, rqst->rq_xprt->xpt_remotebuf) + __string(addr, rqst->rq_xprt ? + rqst->rq_xprt->xpt_remotebuf : "(null)") ), TP_fast_assign( @@ -577,7 +578,8 @@ TRACE_EVENT(svc_process, __entry->vers = rqst->rq_vers; __entry->proc = rqst->rq_proc; __assign_str(service, name); - __assign_str(addr, rqst->rq_xprt->xpt_remotebuf); + __assign_str(addr, rqst->rq_xprt ? + rqst->rq_xprt->xpt_remotebuf : "(null)"); ), TP_printk("addr=%s xid=0x%08x service=%s vers=%u proc=%u", diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index d13e05f1a990..fb647bc01fc5 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1172,7 +1172,8 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) clear_bit(RQ_DROPME, &rqstp->rq_flags); /* Setup reply header */ - rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); + if (rqstp->rq_prot == IPPROTO_TCP) + svc_tcp_prep_reply_hdr(rqstp); svc_putu32(resv, rqstp->rq_xid); @@ -1244,7 +1245,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) * for lower versions. RPC_PROG_MISMATCH seems to be the closest * fit. */ - if (versp->vs_need_cong_ctrl && + if (versp->vs_need_cong_ctrl && rqstp->rq_xprt && !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags)) goto err_bad_vers; @@ -1336,7 +1337,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) return 0; close: - if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags)) + if (rqstp->rq_xprt && test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags)) svc_close_xprt(rqstp->rq_xprt); dprintk("svc: svc_process close\n"); return 0; @@ -1459,10 +1460,10 @@ bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req, dprintk("svc: %s(%p)\n", __func__, req); /* Build the svc_rqst used by the common processing routine */ - rqstp->rq_xprt = serv->sv_bc_xprt; rqstp->rq_xid = req->rq_xid; rqstp->rq_prot = req->rq_xprt->prot; rqstp->rq_server = serv; + rqstp->rq_bc_net = req->rq_xprt->xprt_net; rqstp->rq_addrlen = sizeof(req->rq_xprt->addr); memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen); diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 51d36230b6e3..bd42da287c26 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -468,10 +468,11 @@ static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) */ void svc_reserve(struct svc_rqst *rqstp, int space) { + struct svc_xprt *xprt = rqstp->rq_xprt; + space += rqstp->rq_res.head[0].iov_len; - if (space < rqstp->rq_reserved) { - struct svc_xprt *xprt = rqstp->rq_xprt; + if (xprt && space < rqstp->rq_reserved) { atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); rqstp->rq_reserved = space; diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 986f3ed7d1a2..793149ba1bda 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1173,7 +1173,7 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) /* * Setup response header. TCP has a 4B record length field. */ -static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp) +void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp) { struct kvec *resv = &rqstp->rq_res.head[0];

6 years, 8 months

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FAILED: patch "[PATCH] sunrpc: use-after-free in svc_process_common()" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d4b09acf924b84bae77cad090a9d108e70b43643 Mon Sep 17 00:00:00 2001 From: Vasily Averin <vvs(a)virtuozzo.com> Date: Mon, 24 Dec 2018 14:44:52 +0300 Subject: [PATCH] sunrpc: use-after-free in svc_process_common() if node have NFSv41+ mounts inside several net namespaces it can lead to use-after-free in svc_process_common() svc_process_common() /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE svc_process_common() can use incorrect rqstp->rq_xprt, its caller function bc_svc_process() takes it from serv->sv_bc_xprt. The problem is that serv is global structure but sv_bc_xprt is assigned per-netnamespace. According to Trond, the whole "let's set up rqstp->rq_xprt for the back channel" is nothing but a giant hack in order to work around the fact that svc_process_common() uses it to find the xpt_ops, and perform a couple of (meaningless for the back channel) tests of xpt_flags. All we really need in svc_process_common() is to be able to run rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr() Bruce J Fields points that this xpo_prep_reply_hdr() call is an awfully roundabout way just to do "svc_putnl(resv, 0);" in the tcp case. This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(), now it calls svc_process_common() with rqstp->rq_xprt = NULL. To adjust reply header svc_process_common() just check rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case. To handle rqstp->rq_xprt = NULL case in functions called from svc_process_common() patch intruduces net namespace pointer svc_rqst->rq_bc_net and adjust SVC_NET() definition. Some other function was also adopted to properly handle described case. Signed-off-by: Vasily Averin <vvs(a)virtuozzo.com> Cc: stable(a)vger.kernel.org Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup") Signed-off-by: J. Bruce Fields <bfields(a)redhat.com> diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 73e130a840ce..fdb6b317d974 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -295,9 +295,12 @@ struct svc_rqst { struct svc_cacherep * rq_cacherep; /* cache info */ struct task_struct *rq_task; /* service thread */ spinlock_t rq_lock; /* per-request lock */ + struct net *rq_bc_net; /* pointer to backchannel's + * net namespace + */ }; -#define SVC_NET(svc_rqst) (svc_rqst->rq_xprt->xpt_net) +#define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) /* * Rigorous type checking on sockaddr type conversions diff --git a/include/trace/events/sunrpc.h b/include/trace/events/sunrpc.h index 28e384186c35..8617f4fd6b70 100644 --- a/include/trace/events/sunrpc.h +++ b/include/trace/events/sunrpc.h @@ -569,7 +569,8 @@ TRACE_EVENT(svc_process, __field(u32, vers) __field(u32, proc) __string(service, name) - __string(addr, rqst->rq_xprt->xpt_remotebuf) + __string(addr, rqst->rq_xprt ? + rqst->rq_xprt->xpt_remotebuf : "(null)") ), TP_fast_assign( @@ -577,7 +578,8 @@ TRACE_EVENT(svc_process, __entry->vers = rqst->rq_vers; __entry->proc = rqst->rq_proc; __assign_str(service, name); - __assign_str(addr, rqst->rq_xprt->xpt_remotebuf); + __assign_str(addr, rqst->rq_xprt ? + rqst->rq_xprt->xpt_remotebuf : "(null)"); ), TP_printk("addr=%s xid=0x%08x service=%s vers=%u proc=%u", diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index d13e05f1a990..fb647bc01fc5 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1172,7 +1172,8 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) clear_bit(RQ_DROPME, &rqstp->rq_flags); /* Setup reply header */ - rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); + if (rqstp->rq_prot == IPPROTO_TCP) + svc_tcp_prep_reply_hdr(rqstp); svc_putu32(resv, rqstp->rq_xid); @@ -1244,7 +1245,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) * for lower versions. RPC_PROG_MISMATCH seems to be the closest * fit. */ - if (versp->vs_need_cong_ctrl && + if (versp->vs_need_cong_ctrl && rqstp->rq_xprt && !test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags)) goto err_bad_vers; @@ -1336,7 +1337,7 @@ svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv) return 0; close: - if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags)) + if (rqstp->rq_xprt && test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags)) svc_close_xprt(rqstp->rq_xprt); dprintk("svc: svc_process close\n"); return 0; @@ -1459,10 +1460,10 @@ bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req, dprintk("svc: %s(%p)\n", __func__, req); /* Build the svc_rqst used by the common processing routine */ - rqstp->rq_xprt = serv->sv_bc_xprt; rqstp->rq_xid = req->rq_xid; rqstp->rq_prot = req->rq_xprt->prot; rqstp->rq_server = serv; + rqstp->rq_bc_net = req->rq_xprt->xprt_net; rqstp->rq_addrlen = sizeof(req->rq_xprt->addr); memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen); diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c index 51d36230b6e3..bd42da287c26 100644 --- a/net/sunrpc/svc_xprt.c +++ b/net/sunrpc/svc_xprt.c @@ -468,10 +468,11 @@ static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool) */ void svc_reserve(struct svc_rqst *rqstp, int space) { + struct svc_xprt *xprt = rqstp->rq_xprt; + space += rqstp->rq_res.head[0].iov_len; - if (space < rqstp->rq_reserved) { - struct svc_xprt *xprt = rqstp->rq_xprt; + if (xprt && space < rqstp->rq_reserved) { atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved); rqstp->rq_reserved = space; diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 986f3ed7d1a2..793149ba1bda 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -1173,7 +1173,7 @@ static int svc_tcp_sendto(struct svc_rqst *rqstp) /* * Setup response header. TCP has a 4B record length field. */ -static void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp) +void svc_tcp_prep_reply_hdr(struct svc_rqst *rqstp) { struct kvec *resv = &rqstp->rq_res.head[0];

6 years, 8 months

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FAILED: patch "[PATCH] hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From c86aa7bbfd5568ba8a82d3635d8f7b8a8e06fe54 Mon Sep 17 00:00:00 2001 From: Mike Kravetz <mike.kravetz(a)oracle.com> Date: Fri, 28 Dec 2018 00:39:42 -0800 Subject: [PATCH] hugetlbfs: Use i_mmap_rwsem to fix page fault/truncate race hugetlbfs page faults can race with truncate and hole punch operations. Current code in the page fault path attempts to handle this by 'backing out' operations if we encounter the race. One obvious omission in the current code is removing a page newly added to the page cache. This is pretty straight forward to address, but there is a more subtle and difficult issue of backing out hugetlb reservations. To handle this correctly, the 'reservation state' before page allocation needs to be noted so that it can be properly backed out. There are four distinct possibilities for reservation state: shared/reserved, shared/no-resv, private/reserved and private/no-resv. Backing out a reservation may require memory allocation which could fail so that needs to be taken into account as well. Instead of writing the required complicated code for this rare occurrence, just eliminate the race. i_mmap_rwsem is now held in read mode for the duration of page fault processing. Hold i_mmap_rwsem longer in truncation and hold punch code to cover the call to remove_inode_hugepages. With this modification, code in remove_inode_hugepages checking for races becomes 'dead' as it can not longer happen. Remove the dead code and expand comments to explain reasoning. Similarly, checks for races with truncation in the page fault path can be simplified and removed. [mike.kravetz(a)oracle.com: incorporat suggestions from Kirill] Link: http://lkml.kernel.org/r/20181222223013.22193-3-mike.kravetz@oracle.com Link: http://lkml.kernel.org/r/20181218223557.5202-3-mike.kravetz@oracle.com Fixes: ebed4bfc8da8 ("hugetlb: fix absurd HugePages_Rsvd") Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Hugh Dickins <hughd(a)google.com> Cc: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar(a)linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange(a)redhat.com> Cc: Davidlohr Bueso <dave(a)stgolabs.net> Cc: Prakash Sangappa <prakash.sangappa(a)oracle.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index 32920a10100e..a2fcea5f8225 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -383,17 +383,16 @@ hugetlb_vmdelete_list(struct rb_root_cached *root, pgoff_t start, pgoff_t end) * truncation is indicated by end of range being LLONG_MAX * In this case, we first scan the range and release found pages. * After releasing pages, hugetlb_unreserve_pages cleans up region/reserv - * maps and global counts. Page faults can not race with truncation - * in this routine. hugetlb_no_page() prevents page faults in the - * truncated range. It checks i_size before allocation, and again after - * with the page table lock for the page held. The same lock must be - * acquired to unmap a page. + * maps and global counts. * hole punch is indicated if end is not LLONG_MAX * In the hole punch case we scan the range and release found pages. * Only when releasing a page is the associated region/reserv map * deleted. The region/reserv map for ranges without associated - * pages are not modified. Page faults can race with hole punch. - * This is indicated if we find a mapped page. + * pages are not modified. + * + * Callers of this routine must hold the i_mmap_rwsem in write mode to prevent + * races with page faults. + * * Note: If the passed end of range value is beyond the end of file, but * not LLONG_MAX this routine still performs a hole punch operation. */ @@ -423,32 +422,14 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart, for (i = 0; i < pagevec_count(&pvec); ++i) { struct page *page = pvec.pages[i]; - u32 hash; index = page->index; - hash = hugetlb_fault_mutex_hash(h, current->mm, - &pseudo_vma, - mapping, index, 0); - mutex_lock(&hugetlb_fault_mutex_table[hash]); - /* - * If page is mapped, it was faulted in after being - * unmapped in caller. Unmap (again) now after taking - * the fault mutex. The mutex will prevent faults - * until we finish removing the page. - * - * This race can only happen in the hole punch case. - * Getting here in a truncate operation is a bug. + * A mapped page is impossible as callers should unmap + * all references before calling. And, i_mmap_rwsem + * prevents the creation of additional mappings. */ - if (unlikely(page_mapped(page))) { - BUG_ON(truncate_op); - - i_mmap_lock_write(mapping); - hugetlb_vmdelete_list(&mapping->i_mmap, - index * pages_per_huge_page(h), - (index + 1) * pages_per_huge_page(h)); - i_mmap_unlock_write(mapping); - } + VM_BUG_ON(page_mapped(page)); lock_page(page); /* @@ -470,7 +451,6 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart, } unlock_page(page); - mutex_unlock(&hugetlb_fault_mutex_table[hash]); } huge_pagevec_release(&pvec); cond_resched(); @@ -482,9 +462,20 @@ static void remove_inode_hugepages(struct inode *inode, loff_t lstart, static void hugetlbfs_evict_inode(struct inode *inode) { + struct address_space *mapping = inode->i_mapping; struct resv_map *resv_map; + /* + * The vfs layer guarantees that there are no other users of this + * inode. Therefore, it would be safe to call remove_inode_hugepages + * without holding i_mmap_rwsem. We acquire and hold here to be + * consistent with other callers. Since there will be no contention + * on the semaphore, overhead is negligible. + */ + i_mmap_lock_write(mapping); remove_inode_hugepages(inode, 0, LLONG_MAX); + i_mmap_unlock_write(mapping); + resv_map = (struct resv_map *)inode->i_mapping->private_data; /* root inode doesn't have the resv_map, so we should check it */ if (resv_map) @@ -505,8 +496,8 @@ static int hugetlb_vmtruncate(struct inode *inode, loff_t offset) i_mmap_lock_write(mapping); if (!RB_EMPTY_ROOT(&mapping->i_mmap.rb_root)) hugetlb_vmdelete_list(&mapping->i_mmap, pgoff, 0); - i_mmap_unlock_write(mapping); remove_inode_hugepages(inode, offset, LLONG_MAX); + i_mmap_unlock_write(mapping); return 0; } @@ -540,8 +531,8 @@ static long hugetlbfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) hugetlb_vmdelete_list(&mapping->i_mmap, hole_start >> PAGE_SHIFT, hole_end >> PAGE_SHIFT); - i_mmap_unlock_write(mapping); remove_inode_hugepages(inode, hole_start, hole_end); + i_mmap_unlock_write(mapping); inode_unlock(inode); } @@ -624,7 +615,11 @@ static long hugetlbfs_fallocate(struct file *file, int mode, loff_t offset, /* addr is the offset within the file (zero based) */ addr = index * hpage_size; - /* mutex taken here, fault path and hole punch */ + /* + * fault mutex taken here, protects against fault path + * and hole punch. inode_lock previously taken protects + * against truncation. + */ hash = hugetlb_fault_mutex_hash(h, mm, &pseudo_vma, mapping, index, addr); mutex_lock(&hugetlb_fault_mutex_table[hash]); diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 87fd3ab809c6..e37efd5d8318 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3755,16 +3755,16 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, } /* - * Use page lock to guard against racing truncation - * before we get page_table_lock. + * We can not race with truncation due to holding i_mmap_rwsem. + * Check once here for faults beyond end of file. */ + size = i_size_read(mapping->host) >> huge_page_shift(h); + if (idx >= size) + goto out; + retry: page = find_lock_page(mapping, idx); if (!page) { - size = i_size_read(mapping->host) >> huge_page_shift(h); - if (idx >= size) - goto out; - /* * Check for page in userfault range */ @@ -3854,9 +3854,6 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, } ptl = huge_pte_lock(h, mm, ptep); - size = i_size_read(mapping->host) >> huge_page_shift(h); - if (idx >= size) - goto backout; ret = 0; if (!huge_pte_none(huge_ptep_get(ptep))) @@ -3959,8 +3956,10 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, /* * Acquire i_mmap_rwsem before calling huge_pte_alloc and hold - * until finished with ptep. This prevents huge_pmd_unshare from - * being called elsewhere and making the ptep no longer valid. + * until finished with ptep. This serves two purposes: + * 1) It prevents huge_pmd_unshare from being called elsewhere + * and making the ptep no longer valid. + * 2) It synchronizes us with file truncation. * * ptep could have already be assigned via huge_pte_offset. That * is OK, as huge_pte_alloc will return the same value unless

6 years, 8 months

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FAILED: patch "[PATCH] hugetlbfs: use i_mmap_rwsem for more pmd sharing" failed to apply to 4.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b43a9990055958e70347c56f90ea2ae32c67334c Mon Sep 17 00:00:00 2001 From: Mike Kravetz <mike.kravetz(a)oracle.com> Date: Fri, 28 Dec 2018 00:39:38 -0800 Subject: [PATCH] hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization While looking at BUGs associated with invalid huge page map counts, it was discovered and observed that a huge pte pointer could become 'invalid' and point to another task's page table. Consider the following: A task takes a page fault on a shared hugetlbfs file and calls huge_pte_alloc to get a ptep. Suppose the returned ptep points to a shared pmd. Now, another task truncates the hugetlbfs file. As part of truncation, it unmaps everyone who has the file mapped. If the range being truncated is covered by a shared pmd, huge_pmd_unshare will be called. For all but the last user of the shared pmd, huge_pmd_unshare will clear the pud pointing to the pmd. If the task in the middle of the page fault is not the last user, the ptep returned by huge_pte_alloc now points to another task's page table or worse. This leads to bad things such as incorrect page map/reference counts or invalid memory references. To fix, expand the use of i_mmap_rwsem as follows: - i_mmap_rwsem is held in read mode whenever huge_pmd_share is called. huge_pmd_share is only called via huge_pte_alloc, so callers of huge_pte_alloc take i_mmap_rwsem before calling. In addition, callers of huge_pte_alloc continue to hold the semaphore until finished with the ptep. - i_mmap_rwsem is held in write mode whenever huge_pmd_unshare is called. [mike.kravetz(a)oracle.com: add explicit check for mapping != null] Link: http://lkml.kernel.org/r/20181218223557.5202-2-mike.kravetz@oracle.com Fixes: 39dde65c9940 ("shared page table for hugetlb page") Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Hugh Dickins <hughd(a)google.com> Cc: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar(a)linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange(a)redhat.com> Cc: Davidlohr Bueso <dave(a)stgolabs.net> Cc: Prakash Sangappa <prakash.sangappa(a)oracle.com> Cc: Colin Ian King <colin.king(a)canonical.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 12000ba5c868..87fd3ab809c6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3238,6 +3238,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, struct page *ptepage; unsigned long addr; int cow; + struct address_space *mapping = vma->vm_file->f_mapping; struct hstate *h = hstate_vma(vma); unsigned long sz = huge_page_size(h); struct mmu_notifier_range range; @@ -3249,13 +3250,23 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, mmu_notifier_range_init(&range, src, vma->vm_start, vma->vm_end); mmu_notifier_invalidate_range_start(&range); + } else { + /* + * For shared mappings i_mmap_rwsem must be held to call + * huge_pte_alloc, otherwise the returned ptep could go + * away if part of a shared pmd and another thread calls + * huge_pmd_unshare. + */ + i_mmap_lock_read(mapping); } for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { spinlock_t *src_ptl, *dst_ptl; + src_pte = huge_pte_offset(src, addr, sz); if (!src_pte) continue; + dst_pte = huge_pte_alloc(dst, addr, sz); if (!dst_pte) { ret = -ENOMEM; @@ -3326,6 +3337,8 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, if (cow) mmu_notifier_invalidate_range_end(&range); + else + i_mmap_unlock_read(mapping); return ret; } @@ -3771,14 +3784,18 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, }; /* - * hugetlb_fault_mutex must be dropped before - * handling userfault. Reacquire after handling - * fault to make calling code simpler. + * hugetlb_fault_mutex and i_mmap_rwsem must be + * dropped before handling userfault. Reacquire + * after handling fault to make calling code simpler. */ hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, haddr); mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); + ret = handle_userfault(&vmf, VM_UFFD_MISSING); + + i_mmap_lock_read(mapping); mutex_lock(&hugetlb_fault_mutex_table[hash]); goto out; } @@ -3926,6 +3943,11 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (ptep) { + /* + * Since we hold no locks, ptep could be stale. That is + * OK as we are only making decisions based on content and + * not actually modifying content here. + */ entry = huge_ptep_get(ptep); if (unlikely(is_hugetlb_entry_migration(entry))) { migration_entry_wait_huge(vma, mm, ptep); @@ -3933,20 +3955,31 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) return VM_FAULT_HWPOISON_LARGE | VM_FAULT_SET_HINDEX(hstate_index(h)); - } else { - ptep = huge_pte_alloc(mm, haddr, huge_page_size(h)); - if (!ptep) - return VM_FAULT_OOM; } + /* + * Acquire i_mmap_rwsem before calling huge_pte_alloc and hold + * until finished with ptep. This prevents huge_pmd_unshare from + * being called elsewhere and making the ptep no longer valid. + * + * ptep could have already be assigned via huge_pte_offset. That + * is OK, as huge_pte_alloc will return the same value unless + * something changed. + */ mapping = vma->vm_file->f_mapping; - idx = vma_hugecache_offset(h, vma, haddr); + i_mmap_lock_read(mapping); + ptep = huge_pte_alloc(mm, haddr, huge_page_size(h)); + if (!ptep) { + i_mmap_unlock_read(mapping); + return VM_FAULT_OOM; + } /* * Serialize hugepage allocation and instantiation, so that we don't * get spurious allocation failures if two CPUs race to instantiate * the same page in the page cache. */ + idx = vma_hugecache_offset(h, vma, haddr); hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, haddr); mutex_lock(&hugetlb_fault_mutex_table[hash]); @@ -4034,6 +4067,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, } out_mutex: mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); /* * Generally it's safe to hold refcount during waiting page lock. But * here we just wait to defer the next page fault to avoid busy loop and @@ -4638,10 +4672,12 @@ void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() * and returns the corresponding pte. While this is not necessary for the * !shared pmd case because we can allocate the pmd later as well, it makes the - * code much cleaner. pmd allocation is essential for the shared case because - * pud has to be populated inside the same i_mmap_rwsem section - otherwise - * racing tasks could either miss the sharing (see huge_pte_offset) or select a - * bad pmd for sharing. + * code much cleaner. + * + * This routine must be called with i_mmap_rwsem held in at least read mode. + * For hugetlbfs, this prevents removal of any page table entries associated + * with the address space. This is important as we are setting up sharing + * based on existing page table entries (mappings). */ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) { @@ -4658,7 +4694,6 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) if (!vma_shareable(vma, addr)) return (pte_t *)pmd_alloc(mm, pud, addr); - i_mmap_lock_write(mapping); vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { if (svma == vma) continue; @@ -4688,7 +4723,6 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) spin_unlock(ptl); out: pte = (pte_t *)pmd_alloc(mm, pud, addr); - i_mmap_unlock_write(mapping); return pte; } @@ -4699,7 +4733,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) * indicated by page_count > 1, unmap is achieved by clearing pud and * decrementing the ref count. If count == 1, the pte page is not shared. * - * called with page table lock held. + * Called with page table lock held and i_mmap_rwsem held in write mode. * * returns: 1 successfully unmapped a shared pte page * 0 the underlying pte page is not shared, or it is the last user diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 7c72f2a95785..6379fff1a5ff 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -966,7 +966,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; struct address_space *mapping; LIST_HEAD(tokill); - bool unmap_success; + bool unmap_success = true; int kill = 1, forcekill; struct page *hpage = *hpagep; bool mlocked = PageMlocked(hpage); @@ -1028,7 +1028,19 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, if (kill) collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED); - unmap_success = try_to_unmap(hpage, ttu); + if (!PageHuge(hpage)) { + unmap_success = try_to_unmap(hpage, ttu); + } else if (mapping) { + /* + * For hugetlb pages, try_to_unmap could potentially call + * huge_pmd_unshare. Because of this, take semaphore in + * write mode here and set TTU_RMAP_LOCKED to indicate we + * have taken the lock at this higer level. + */ + i_mmap_lock_write(mapping); + unmap_success = try_to_unmap(hpage, ttu|TTU_RMAP_LOCKED); + i_mmap_unlock_write(mapping); + } if (!unmap_success) pr_err("Memory failure: %#lx: failed to unmap page (mapcount=%d)\n", pfn, page_mapcount(hpage)); diff --git a/mm/migrate.c b/mm/migrate.c index 4389696fba0e..5d1839a9148d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1324,8 +1324,19 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, goto put_anon; if (page_mapped(hpage)) { + struct address_space *mapping = page_mapping(hpage); + + /* + * try_to_unmap could potentially call huge_pmd_unshare. + * Because of this, take semaphore in write mode here and + * set TTU_RMAP_LOCKED to let lower levels know we have + * taken the lock. + */ + i_mmap_lock_write(mapping); try_to_unmap(hpage, - TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); + TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS| + TTU_RMAP_LOCKED); + i_mmap_unlock_write(mapping); page_was_mapped = 1; } diff --git a/mm/rmap.c b/mm/rmap.c index 68a1a5b869a5..21a26cf51114 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -25,6 +25,7 @@ * page->flags PG_locked (lock_page) * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) * mapping->i_mmap_rwsem + * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) * anon_vma->rwsem * mm->page_table_lock or pte_lock * zone_lru_lock (in mark_page_accessed, isolate_lru_page) @@ -1378,6 +1379,9 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, /* * If sharing is possible, start and end will be adjusted * accordingly. + * + * If called for a huge page, caller must hold i_mmap_rwsem + * in write mode as it is possible to call huge_pmd_unshare. */ adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 458acda96f20..48368589f519 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -267,10 +267,14 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, VM_BUG_ON(dst_addr & ~huge_page_mask(h)); /* - * Serialize via hugetlb_fault_mutex + * Serialize via i_mmap_rwsem and hugetlb_fault_mutex. + * i_mmap_rwsem ensures the dst_pte remains valid even + * in the case of shared pmds. fault mutex prevents + * races with other faulting threads. */ - idx = linear_page_index(dst_vma, dst_addr); mapping = dst_vma->vm_file->f_mapping; + i_mmap_lock_read(mapping); + idx = linear_page_index(dst_vma, dst_addr); hash = hugetlb_fault_mutex_hash(h, dst_mm, dst_vma, mapping, idx, dst_addr); mutex_lock(&hugetlb_fault_mutex_table[hash]); @@ -279,6 +283,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h)); if (!dst_pte) { mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); goto out_unlock; } @@ -286,6 +291,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_pteval = huge_ptep_get(dst_pte); if (!huge_pte_none(dst_pteval)) { mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); goto out_unlock; } @@ -293,6 +299,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_addr, src_addr, &page); mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); vm_alloc_shared = vm_shared; cond_resched();

6 years, 8 months

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FAILED: patch "[PATCH] hugetlbfs: use i_mmap_rwsem for more pmd sharing" failed to apply to 4.9-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From b43a9990055958e70347c56f90ea2ae32c67334c Mon Sep 17 00:00:00 2001 From: Mike Kravetz <mike.kravetz(a)oracle.com> Date: Fri, 28 Dec 2018 00:39:38 -0800 Subject: [PATCH] hugetlbfs: use i_mmap_rwsem for more pmd sharing synchronization While looking at BUGs associated with invalid huge page map counts, it was discovered and observed that a huge pte pointer could become 'invalid' and point to another task's page table. Consider the following: A task takes a page fault on a shared hugetlbfs file and calls huge_pte_alloc to get a ptep. Suppose the returned ptep points to a shared pmd. Now, another task truncates the hugetlbfs file. As part of truncation, it unmaps everyone who has the file mapped. If the range being truncated is covered by a shared pmd, huge_pmd_unshare will be called. For all but the last user of the shared pmd, huge_pmd_unshare will clear the pud pointing to the pmd. If the task in the middle of the page fault is not the last user, the ptep returned by huge_pte_alloc now points to another task's page table or worse. This leads to bad things such as incorrect page map/reference counts or invalid memory references. To fix, expand the use of i_mmap_rwsem as follows: - i_mmap_rwsem is held in read mode whenever huge_pmd_share is called. huge_pmd_share is only called via huge_pte_alloc, so callers of huge_pte_alloc take i_mmap_rwsem before calling. In addition, callers of huge_pte_alloc continue to hold the semaphore until finished with the ptep. - i_mmap_rwsem is held in write mode whenever huge_pmd_unshare is called. [mike.kravetz(a)oracle.com: add explicit check for mapping != null] Link: http://lkml.kernel.org/r/20181218223557.5202-2-mike.kravetz@oracle.com Fixes: 39dde65c9940 ("shared page table for hugetlb page") Signed-off-by: Mike Kravetz <mike.kravetz(a)oracle.com> Acked-by: Kirill A. Shutemov <kirill.shutemov(a)linux.intel.com> Cc: Michal Hocko <mhocko(a)kernel.org> Cc: Hugh Dickins <hughd(a)google.com> Cc: Naoya Horiguchi <n-horiguchi(a)ah.jp.nec.com> Cc: "Aneesh Kumar K . V" <aneesh.kumar(a)linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange(a)redhat.com> Cc: Davidlohr Bueso <dave(a)stgolabs.net> Cc: Prakash Sangappa <prakash.sangappa(a)oracle.com> Cc: Colin Ian King <colin.king(a)canonical.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 12000ba5c868..87fd3ab809c6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3238,6 +3238,7 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, struct page *ptepage; unsigned long addr; int cow; + struct address_space *mapping = vma->vm_file->f_mapping; struct hstate *h = hstate_vma(vma); unsigned long sz = huge_page_size(h); struct mmu_notifier_range range; @@ -3249,13 +3250,23 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, mmu_notifier_range_init(&range, src, vma->vm_start, vma->vm_end); mmu_notifier_invalidate_range_start(&range); + } else { + /* + * For shared mappings i_mmap_rwsem must be held to call + * huge_pte_alloc, otherwise the returned ptep could go + * away if part of a shared pmd and another thread calls + * huge_pmd_unshare. + */ + i_mmap_lock_read(mapping); } for (addr = vma->vm_start; addr < vma->vm_end; addr += sz) { spinlock_t *src_ptl, *dst_ptl; + src_pte = huge_pte_offset(src, addr, sz); if (!src_pte) continue; + dst_pte = huge_pte_alloc(dst, addr, sz); if (!dst_pte) { ret = -ENOMEM; @@ -3326,6 +3337,8 @@ int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src, if (cow) mmu_notifier_invalidate_range_end(&range); + else + i_mmap_unlock_read(mapping); return ret; } @@ -3771,14 +3784,18 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm, }; /* - * hugetlb_fault_mutex must be dropped before - * handling userfault. Reacquire after handling - * fault to make calling code simpler. + * hugetlb_fault_mutex and i_mmap_rwsem must be + * dropped before handling userfault. Reacquire + * after handling fault to make calling code simpler. */ hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, haddr); mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); + ret = handle_userfault(&vmf, VM_UFFD_MISSING); + + i_mmap_lock_read(mapping); mutex_lock(&hugetlb_fault_mutex_table[hash]); goto out; } @@ -3926,6 +3943,11 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, ptep = huge_pte_offset(mm, haddr, huge_page_size(h)); if (ptep) { + /* + * Since we hold no locks, ptep could be stale. That is + * OK as we are only making decisions based on content and + * not actually modifying content here. + */ entry = huge_ptep_get(ptep); if (unlikely(is_hugetlb_entry_migration(entry))) { migration_entry_wait_huge(vma, mm, ptep); @@ -3933,20 +3955,31 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, } else if (unlikely(is_hugetlb_entry_hwpoisoned(entry))) return VM_FAULT_HWPOISON_LARGE | VM_FAULT_SET_HINDEX(hstate_index(h)); - } else { - ptep = huge_pte_alloc(mm, haddr, huge_page_size(h)); - if (!ptep) - return VM_FAULT_OOM; } + /* + * Acquire i_mmap_rwsem before calling huge_pte_alloc and hold + * until finished with ptep. This prevents huge_pmd_unshare from + * being called elsewhere and making the ptep no longer valid. + * + * ptep could have already be assigned via huge_pte_offset. That + * is OK, as huge_pte_alloc will return the same value unless + * something changed. + */ mapping = vma->vm_file->f_mapping; - idx = vma_hugecache_offset(h, vma, haddr); + i_mmap_lock_read(mapping); + ptep = huge_pte_alloc(mm, haddr, huge_page_size(h)); + if (!ptep) { + i_mmap_unlock_read(mapping); + return VM_FAULT_OOM; + } /* * Serialize hugepage allocation and instantiation, so that we don't * get spurious allocation failures if two CPUs race to instantiate * the same page in the page cache. */ + idx = vma_hugecache_offset(h, vma, haddr); hash = hugetlb_fault_mutex_hash(h, mm, vma, mapping, idx, haddr); mutex_lock(&hugetlb_fault_mutex_table[hash]); @@ -4034,6 +4067,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, } out_mutex: mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); /* * Generally it's safe to hold refcount during waiting page lock. But * here we just wait to defer the next page fault to avoid busy loop and @@ -4638,10 +4672,12 @@ void adjust_range_if_pmd_sharing_possible(struct vm_area_struct *vma, * Search for a shareable pmd page for hugetlb. In any case calls pmd_alloc() * and returns the corresponding pte. While this is not necessary for the * !shared pmd case because we can allocate the pmd later as well, it makes the - * code much cleaner. pmd allocation is essential for the shared case because - * pud has to be populated inside the same i_mmap_rwsem section - otherwise - * racing tasks could either miss the sharing (see huge_pte_offset) or select a - * bad pmd for sharing. + * code much cleaner. + * + * This routine must be called with i_mmap_rwsem held in at least read mode. + * For hugetlbfs, this prevents removal of any page table entries associated + * with the address space. This is important as we are setting up sharing + * based on existing page table entries (mappings). */ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) { @@ -4658,7 +4694,6 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) if (!vma_shareable(vma, addr)) return (pte_t *)pmd_alloc(mm, pud, addr); - i_mmap_lock_write(mapping); vma_interval_tree_foreach(svma, &mapping->i_mmap, idx, idx) { if (svma == vma) continue; @@ -4688,7 +4723,6 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) spin_unlock(ptl); out: pte = (pte_t *)pmd_alloc(mm, pud, addr); - i_mmap_unlock_write(mapping); return pte; } @@ -4699,7 +4733,7 @@ pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud) * indicated by page_count > 1, unmap is achieved by clearing pud and * decrementing the ref count. If count == 1, the pte page is not shared. * - * called with page table lock held. + * Called with page table lock held and i_mmap_rwsem held in write mode. * * returns: 1 successfully unmapped a shared pte page * 0 the underlying pte page is not shared, or it is the last user diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 7c72f2a95785..6379fff1a5ff 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -966,7 +966,7 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, enum ttu_flags ttu = TTU_IGNORE_MLOCK | TTU_IGNORE_ACCESS; struct address_space *mapping; LIST_HEAD(tokill); - bool unmap_success; + bool unmap_success = true; int kill = 1, forcekill; struct page *hpage = *hpagep; bool mlocked = PageMlocked(hpage); @@ -1028,7 +1028,19 @@ static bool hwpoison_user_mappings(struct page *p, unsigned long pfn, if (kill) collect_procs(hpage, &tokill, flags & MF_ACTION_REQUIRED); - unmap_success = try_to_unmap(hpage, ttu); + if (!PageHuge(hpage)) { + unmap_success = try_to_unmap(hpage, ttu); + } else if (mapping) { + /* + * For hugetlb pages, try_to_unmap could potentially call + * huge_pmd_unshare. Because of this, take semaphore in + * write mode here and set TTU_RMAP_LOCKED to indicate we + * have taken the lock at this higer level. + */ + i_mmap_lock_write(mapping); + unmap_success = try_to_unmap(hpage, ttu|TTU_RMAP_LOCKED); + i_mmap_unlock_write(mapping); + } if (!unmap_success) pr_err("Memory failure: %#lx: failed to unmap page (mapcount=%d)\n", pfn, page_mapcount(hpage)); diff --git a/mm/migrate.c b/mm/migrate.c index 4389696fba0e..5d1839a9148d 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -1324,8 +1324,19 @@ static int unmap_and_move_huge_page(new_page_t get_new_page, goto put_anon; if (page_mapped(hpage)) { + struct address_space *mapping = page_mapping(hpage); + + /* + * try_to_unmap could potentially call huge_pmd_unshare. + * Because of this, take semaphore in write mode here and + * set TTU_RMAP_LOCKED to let lower levels know we have + * taken the lock. + */ + i_mmap_lock_write(mapping); try_to_unmap(hpage, - TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS); + TTU_MIGRATION|TTU_IGNORE_MLOCK|TTU_IGNORE_ACCESS| + TTU_RMAP_LOCKED); + i_mmap_unlock_write(mapping); page_was_mapped = 1; } diff --git a/mm/rmap.c b/mm/rmap.c index 68a1a5b869a5..21a26cf51114 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -25,6 +25,7 @@ * page->flags PG_locked (lock_page) * hugetlbfs_i_mmap_rwsem_key (in huge_pmd_share) * mapping->i_mmap_rwsem + * hugetlb_fault_mutex (hugetlbfs specific page fault mutex) * anon_vma->rwsem * mm->page_table_lock or pte_lock * zone_lru_lock (in mark_page_accessed, isolate_lru_page) @@ -1378,6 +1379,9 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma, /* * If sharing is possible, start and end will be adjusted * accordingly. + * + * If called for a huge page, caller must hold i_mmap_rwsem + * in write mode as it is possible to call huge_pmd_unshare. */ adjust_range_if_pmd_sharing_possible(vma, &range.start, &range.end); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 458acda96f20..48368589f519 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -267,10 +267,14 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, VM_BUG_ON(dst_addr & ~huge_page_mask(h)); /* - * Serialize via hugetlb_fault_mutex + * Serialize via i_mmap_rwsem and hugetlb_fault_mutex. + * i_mmap_rwsem ensures the dst_pte remains valid even + * in the case of shared pmds. fault mutex prevents + * races with other faulting threads. */ - idx = linear_page_index(dst_vma, dst_addr); mapping = dst_vma->vm_file->f_mapping; + i_mmap_lock_read(mapping); + idx = linear_page_index(dst_vma, dst_addr); hash = hugetlb_fault_mutex_hash(h, dst_mm, dst_vma, mapping, idx, dst_addr); mutex_lock(&hugetlb_fault_mutex_table[hash]); @@ -279,6 +283,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_pte = huge_pte_alloc(dst_mm, dst_addr, huge_page_size(h)); if (!dst_pte) { mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); goto out_unlock; } @@ -286,6 +291,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_pteval = huge_ptep_get(dst_pte); if (!huge_pte_none(dst_pteval)) { mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); goto out_unlock; } @@ -293,6 +299,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm, dst_addr, src_addr, &page); mutex_unlock(&hugetlb_fault_mutex_table[hash]); + i_mmap_unlock_read(mapping); vm_alloc_shared = vm_shared; cond_resched();

6 years, 8 months

1
0
0 0

FAILED: patch "[PATCH] mm, hmm: replace hmm_devmem_pages_create() with" failed to apply to 4.19-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From bbecd94e6c514a1559fc1a7749a62715958137b1 Mon Sep 17 00:00:00 2001 From: Dan Williams <dan.j.williams(a)intel.com> Date: Fri, 28 Dec 2018 00:35:11 -0800 Subject: [PATCH] mm, hmm: replace hmm_devmem_pages_create() with devm_memremap_pages() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit e8d513483300 ("memremap: change devm_memremap_pages interface to use struct dev_pagemap") refactored devm_memremap_pages() to allow a dev_pagemap instance to be supplied. Passing in a dev_pagemap interface simplifies the design of pgmap type drivers in that they can rely on container_of() to lookup any private data associated with the given dev_pagemap instance. In addition to the cleanups this also gives hmm users multi-order-radix improvements that arrived with commit ab1b597ee0e4 "mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups" As part of the conversion to the devm_memremap_pages() method of handling the percpu_ref relative to when pages are put, the percpu_ref completion needs to move to hmm_devmem_ref_exit(). See 71389703839e ("mm, zone_device: Replace {get, put}_zone_device_page...") for details. Link: http://lkml.kernel.org/r/154275560053.76910.10870962637383152392.stgit@dwil… Signed-off-by: Dan Williams <dan.j.williams(a)intel.com> Reviewed-by: Christoph Hellwig <hch(a)lst.de> Reviewed-by: Jérôme Glisse <jglisse(a)redhat.com> Acked-by: Balbir Singh <bsingharora(a)gmail.com> Cc: Logan Gunthorpe <logang(a)deltatee.com> Cc: Michal Hocko <mhocko(a)suse.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> diff --git a/mm/hmm.c b/mm/hmm.c index 8510881e7b44..bf2495d9de81 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -986,17 +986,16 @@ static void hmm_devmem_ref_exit(void *data) struct hmm_devmem *devmem; devmem = container_of(ref, struct hmm_devmem, ref); + wait_for_completion(&devmem->completion); percpu_ref_exit(ref); } -static void hmm_devmem_ref_kill(void *data) +static void hmm_devmem_ref_kill(struct percpu_ref *ref) { - struct percpu_ref *ref = data; struct hmm_devmem *devmem; devmem = container_of(ref, struct hmm_devmem, ref); percpu_ref_kill(ref); - wait_for_completion(&devmem->completion); } static int hmm_devmem_fault(struct vm_area_struct *vma, @@ -1019,154 +1018,6 @@ static void hmm_devmem_free(struct page *page, void *data) devmem->ops->free(devmem, page); } -static DEFINE_MUTEX(hmm_devmem_lock); -static RADIX_TREE(hmm_devmem_radix, GFP_KERNEL); - -static void hmm_devmem_radix_release(struct resource *resource) -{ - resource_size_t key; - - mutex_lock(&hmm_devmem_lock); - for (key = resource->start; - key <= resource->end; - key += PA_SECTION_SIZE) - radix_tree_delete(&hmm_devmem_radix, key >> PA_SECTION_SHIFT); - mutex_unlock(&hmm_devmem_lock); -} - -static void hmm_devmem_release(void *data) -{ - struct hmm_devmem *devmem = data; - struct resource *resource = devmem->resource; - unsigned long start_pfn, npages; - struct zone *zone; - struct page *page; - - /* pages are dead and unused, undo the arch mapping */ - start_pfn = (resource->start & ~(PA_SECTION_SIZE - 1)) >> PAGE_SHIFT; - npages = ALIGN(resource_size(resource), PA_SECTION_SIZE) >> PAGE_SHIFT; - - page = pfn_to_page(start_pfn); - zone = page_zone(page); - - mem_hotplug_begin(); - if (resource->desc == IORES_DESC_DEVICE_PRIVATE_MEMORY) - __remove_pages(zone, start_pfn, npages, NULL); - else - arch_remove_memory(start_pfn << PAGE_SHIFT, - npages << PAGE_SHIFT, NULL); - mem_hotplug_done(); - - hmm_devmem_radix_release(resource); -} - -static int hmm_devmem_pages_create(struct hmm_devmem *devmem) -{ - resource_size_t key, align_start, align_size, align_end; - struct device *device = devmem->device; - int ret, nid, is_ram; - - align_start = devmem->resource->start & ~(PA_SECTION_SIZE - 1); - align_size = ALIGN(devmem->resource->start + - resource_size(devmem->resource), - PA_SECTION_SIZE) - align_start; - - is_ram = region_intersects(align_start, align_size, - IORESOURCE_SYSTEM_RAM, - IORES_DESC_NONE); - if (is_ram == REGION_MIXED) { - WARN_ONCE(1, "%s attempted on mixed region %pr\n", - __func__, devmem->resource); - return -ENXIO; - } - if (is_ram == REGION_INTERSECTS) - return -ENXIO; - - if (devmem->resource->desc == IORES_DESC_DEVICE_PUBLIC_MEMORY) - devmem->pagemap.type = MEMORY_DEVICE_PUBLIC; - else - devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; - - devmem->pagemap.res = *devmem->resource; - devmem->pagemap.page_fault = hmm_devmem_fault; - devmem->pagemap.page_free = hmm_devmem_free; - devmem->pagemap.dev = devmem->device; - devmem->pagemap.ref = &devmem->ref; - devmem->pagemap.data = devmem; - - mutex_lock(&hmm_devmem_lock); - align_end = align_start + align_size - 1; - for (key = align_start; key <= align_end; key += PA_SECTION_SIZE) { - struct hmm_devmem *dup; - - dup = radix_tree_lookup(&hmm_devmem_radix, - key >> PA_SECTION_SHIFT); - if (dup) { - dev_err(device, "%s: collides with mapping for %s\n", - __func__, dev_name(dup->device)); - mutex_unlock(&hmm_devmem_lock); - ret = -EBUSY; - goto error; - } - ret = radix_tree_insert(&hmm_devmem_radix, - key >> PA_SECTION_SHIFT, - devmem); - if (ret) { - dev_err(device, "%s: failed: %d\n", __func__, ret); - mutex_unlock(&hmm_devmem_lock); - goto error_radix; - } - } - mutex_unlock(&hmm_devmem_lock); - - nid = dev_to_node(device); - if (nid < 0) - nid = numa_mem_id(); - - mem_hotplug_begin(); - /* - * For device private memory we call add_pages() as we only need to - * allocate and initialize struct page for the device memory. More- - * over the device memory is un-accessible thus we do not want to - * create a linear mapping for the memory like arch_add_memory() - * would do. - * - * For device public memory, which is accesible by the CPU, we do - * want the linear mapping and thus use arch_add_memory(). - */ - if (devmem->pagemap.type == MEMORY_DEVICE_PUBLIC) - ret = arch_add_memory(nid, align_start, align_size, NULL, - false); - else - ret = add_pages(nid, align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, NULL, false); - if (ret) { - mem_hotplug_done(); - goto error_add_memory; - } - move_pfn_range_to_zone(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], - align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, NULL); - mem_hotplug_done(); - - /* - * Initialization of the pages has been deferred until now in order - * to allow us to do the work while not holding the hotplug lock. - */ - memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], - align_start >> PAGE_SHIFT, - align_size >> PAGE_SHIFT, &devmem->pagemap); - - return 0; - -error_add_memory: - untrack_pfn(NULL, PHYS_PFN(align_start), align_size); -error_radix: - hmm_devmem_radix_release(devmem->resource); -error: - return ret; -} - /* * hmm_devmem_add() - hotplug ZONE_DEVICE memory for device memory * @@ -1190,6 +1041,7 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, { struct hmm_devmem *devmem; resource_size_t addr; + void *result; int ret; dev_pagemap_get_ops(); @@ -1244,14 +1096,18 @@ struct hmm_devmem *hmm_devmem_add(const struct hmm_devmem_ops *ops, devmem->pfn_last = devmem->pfn_first + (resource_size(devmem->resource) >> PAGE_SHIFT); - ret = hmm_devmem_pages_create(devmem); - if (ret) - return ERR_PTR(ret); - - ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); - if (ret) - return ERR_PTR(ret); + devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; + devmem->pagemap.res = *devmem->resource; + devmem->pagemap.page_fault = hmm_devmem_fault; + devmem->pagemap.page_free = hmm_devmem_free; + devmem->pagemap.altmap_valid = false; + devmem->pagemap.ref = &devmem->ref; + devmem->pagemap.data = devmem; + devmem->pagemap.kill = hmm_devmem_ref_kill; + result = devm_memremap_pages(devmem->device, &devmem->pagemap); + if (IS_ERR(result)) + return result; return devmem; } EXPORT_SYMBOL(hmm_devmem_add); @@ -1261,6 +1117,7 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, struct resource *res) { struct hmm_devmem *devmem; + void *result; int ret; if (res->desc != IORES_DESC_DEVICE_PUBLIC_MEMORY) @@ -1293,19 +1150,18 @@ struct hmm_devmem *hmm_devmem_add_resource(const struct hmm_devmem_ops *ops, devmem->pfn_last = devmem->pfn_first + (resource_size(devmem->resource) >> PAGE_SHIFT); - ret = hmm_devmem_pages_create(devmem); - if (ret) - return ERR_PTR(ret); - - ret = devm_add_action_or_reset(device, hmm_devmem_release, devmem); - if (ret) - return ERR_PTR(ret); - - ret = devm_add_action_or_reset(device, hmm_devmem_ref_kill, - &devmem->ref); - if (ret) - return ERR_PTR(ret); + devmem->pagemap.type = MEMORY_DEVICE_PUBLIC; + devmem->pagemap.res = *devmem->resource; + devmem->pagemap.page_fault = hmm_devmem_fault; + devmem->pagemap.page_free = hmm_devmem_free; + devmem->pagemap.altmap_valid = false; + devmem->pagemap.ref = &devmem->ref; + devmem->pagemap.data = devmem; + devmem->pagemap.kill = hmm_devmem_ref_kill; + result = devm_memremap_pages(devmem->device, &devmem->pagemap); + if (IS_ERR(result)) + return result; return devmem; } EXPORT_SYMBOL(hmm_devmem_add_resource);

6 years, 8 months

1
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v4.20.1 build: 0 failures 4 warnings (v4.20.1)

by Build bot for Mark Brown

Tree/Branch: v4.20.1 Git describe: v4.20.1 Commit: 8c3f48e8c2 Linux 4.20.1 Build Time: 130 min 9 sec Passed: 11 / 11 (100.00 %) Failed: 0 / 11 ( 0.00 %) Errors: 0 Warnings: 4 Section Mismatches: 0 ------------------------------------------------------------------------------- defconfigs with issues (other than build errors): 1 warnings 0 mismatches : arm64-allmodconfig 3 warnings 0 mismatches : arm-allmodconfig ------------------------------------------------------------------------------- Warnings Summary: 4 1 ../drivers/staging/erofs/unzip_vle.c:188:29: warning: array subscript is above array bounds [-Warray-bounds] 1 ../drivers/scsi/myrs.c:821:24: warning: 'sshdr.sense_key' may be used uninitialized in this function [-Wmaybe-uninitialized] 1 ../drivers/net/ethernet/mellanox/mlx5/core/en_stats.c:216:1: warning: the frame size of 1064 bytes is larger than 1024 bytes [-Wframe-larger-than=] 1 ../drivers/isdn/hardware/eicon/message.c:5985:1: warning: the frame size of 2064 bytes is larger than 2048 bytes [-Wframe-larger-than=] =============================================================================== Detailed per-defconfig build reports below: ------------------------------------------------------------------------------- arm64-allmodconfig : PASS, 0 errors, 1 warnings, 0 section mismatches Warnings: ../drivers/isdn/hardware/eicon/message.c:5985:1: warning: the frame size of 2064 bytes is larger than 2048 bytes [-Wframe-larger-than=] ------------------------------------------------------------------------------- arm-allmodconfig : PASS, 0 errors, 3 warnings, 0 section mismatches Warnings: ../drivers/net/ethernet/mellanox/mlx5/core/en_stats.c:216:1: warning: the frame size of 1064 bytes is larger than 1024 bytes [-Wframe-larger-than=] ../drivers/scsi/myrs.c:821:24: warning: 'sshdr.sense_key' may be used uninitialized in this function [-Wmaybe-uninitialized] ../drivers/staging/erofs/unzip_vle.c:188:29: warning: array subscript is above array bounds [-Warray-bounds] ------------------------------------------------------------------------------- Passed with no errors, warnings or mismatches: arm64-allnoconfig arm-multi_v5_defconfig arm-multi_v7_defconfig x86_64-defconfig arm-allnoconfig x86_64-allnoconfig arm-multi_v4t_defconfig x86_64-allmodconfig arm64-defconfig

6 years, 8 months

1
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0 0

[PATCH v4 1/2] crypto: talitos - reorder code in talitos_edesc_alloc()

by Christophe Leroy

This patch moves the mapping of IV after the kmalloc(). This avoids having to unmap in case kmalloc() fails. Signed-off-by: Christophe Leroy <christophe.leroy(a)c-s.fr> --- new in v4 drivers/crypto/talitos.c | 25 +++++++------------------ 1 file changed, 7 insertions(+), 18 deletions(-) diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c index 45e20707cef8..54d80e7edb86 100644 --- a/drivers/crypto/talitos.c +++ b/drivers/crypto/talitos.c @@ -1361,23 +1361,18 @@ static struct talitos_edesc *talitos_edesc_alloc(struct device *dev, struct talitos_private *priv = dev_get_drvdata(dev); bool is_sec1 = has_ftr_sec1(priv); int max_len = is_sec1 ? TALITOS1_MAX_DATA_LEN : TALITOS2_MAX_DATA_LEN; - void *err; if (cryptlen + authsize > max_len) { dev_err(dev, "length exceeds h/w max limit\n"); return ERR_PTR(-EINVAL); } - if (ivsize) - iv_dma = dma_map_single(dev, iv, ivsize, DMA_TO_DEVICE); - if (!dst || dst == src) { src_len = assoclen + cryptlen + authsize; src_nents = sg_nents_for_len(src, src_len); if (src_nents < 0) { dev_err(dev, "Invalid number of src SG.\n"); - err = ERR_PTR(-EINVAL); - goto error_sg; + return ERR_PTR(-EINVAL); } src_nents = (src_nents == 1) ? 0 : src_nents; dst_nents = dst ? src_nents : 0; @@ -1387,16 +1382,14 @@ static struct talitos_edesc *talitos_edesc_alloc(struct device *dev, src_nents = sg_nents_for_len(src, src_len); if (src_nents < 0) { dev_err(dev, "Invalid number of src SG.\n"); - err = ERR_PTR(-EINVAL); - goto error_sg; + return ERR_PTR(-EINVAL); } src_nents = (src_nents == 1) ? 0 : src_nents; dst_len = assoclen + cryptlen + (encrypt ? authsize : 0); dst_nents = sg_nents_for_len(dst, dst_len); if (dst_nents < 0) { dev_err(dev, "Invalid number of dst SG.\n"); - err = ERR_PTR(-EINVAL); - goto error_sg; + return ERR_PTR(-EINVAL); } dst_nents = (dst_nents == 1) ? 0 : dst_nents; } @@ -1425,10 +1418,10 @@ static struct talitos_edesc *talitos_edesc_alloc(struct device *dev, alloc_len += sizeof(struct talitos_desc); edesc = kmalloc(alloc_len, GFP_DMA | flags); - if (!edesc) { - err = ERR_PTR(-ENOMEM); - goto error_sg; - } + if (!edesc) + return ERR_PTR(-ENOMEM); + if (ivsize) + iv_dma = dma_map_single(dev, iv, ivsize, DMA_TO_DEVICE); memset(&edesc->desc, 0, sizeof(edesc->desc)); edesc->src_nents = src_nents; @@ -1445,10 +1438,6 @@ static struct talitos_edesc *talitos_edesc_alloc(struct device *dev, DMA_BIDIRECTIONAL); } return edesc; -error_sg: - if (iv_dma) - dma_unmap_single(dev, iv_dma, ivsize, DMA_TO_DEVICE); - return err; } static struct talitos_edesc *aead_edesc_alloc(struct aead_request *areq, u8 *iv, -- 2.13.3

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