The patch titled kcore-fix-vread-vwrite-to-be-aware-of-holes-update has been added to the -mm tree. Its filename is kcore-fix-vread-vwrite-to-be-aware-of-holes-update.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: kcore-fix-vread-vwrite-to-be-aware-of-holes-update From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Changelov v3->v3.1 - fixed comments. (mainly vread/vwrite description is updated.) - use KM_USER0 instead of KM_USER1 Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Reviewed-by: WANG Cong <xiyou.wangcong@xxxxxxxxx> Cc: Mike Smith <scgtrp@xxxxxxxxx> Cc: Nick Piggin <nickpiggin@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmalloc.c | 49 +++++++++++++++++++++++++++++++++---------------- 1 file changed, 33 insertions(+), 16 deletions(-) diff -puN mm/vmalloc.c~kcore-fix-vread-vwrite-to-be-aware-of-holes-update mm/vmalloc.c --- a/mm/vmalloc.c~kcore-fix-vread-vwrite-to-be-aware-of-holes-update +++ a/mm/vmalloc.c @@ -1653,10 +1653,13 @@ static int aligned_vread(char *buf, char * kmap() and get small overhead in this access function. */ if (p) { - /* we can expect USR1 is not used */ - void *map = kmap_atomic(p, KM_USER1); + /* + * we can expect USER0 is not used (see vread/vwrite's + * function description) + */ + void *map = kmap_atomic(p, KM_USER0); memcpy(buf, map + offset, length); - kunmap_atomic(map, KM_USER1); + kunmap_atomic(map, KM_USER0); } else memset(buf, 0, length); @@ -1689,10 +1692,13 @@ static int aligned_vwrite(char *buf, cha * kmap() and get small overhead in this access function. */ if (p) { - /* we can expect USR1 is not used */ - void *map = kmap_atomic(p, KM_USER1); + /* + * we can expect USER0 is not used (see vread/vwrite's + * function description) + */ + void *map = kmap_atomic(p, KM_USER0); memcpy(map + offset, buf, length); - kunmap_atomic(map, KM_USER1); + kunmap_atomic(map, KM_USER0); } addr += length; buf += length; @@ -1709,20 +1715,25 @@ static int aligned_vwrite(char *buf, cha * @count: number of bytes to be read. * * Returns # of bytes which addr and buf should be increased. - * (same to count). - * If [addr...addr+count) doesn't includes any valid area, returns 0. + * (same number to @count). Returns 0 if [addr...addr+count) doesn't + * includes any intersect with alive vmalloc area. * * This function checks that addr is a valid vmalloc'ed area, and - * copy data from that area to a given buffer. If the given memory range of - * [addr...addr+count) includes some valid address, data is copied to + * copy data from that area to a given buffer. If the given memory range + * of [addr...addr+count) includes some valid address, data is copied to * proper area of @buf. If there are memory holes, they'll be zero-filled. * IOREMAP area is treated as memory hole and no copy is done. * - * Note: In usual ops, vread() is never necessary because the caller should - * know vmalloc() area is valid and can use memcpy(). This is for routines - * which have to access vmalloc area without any informaion, as /dev/kmem. + * If [addr...addr+count) doesn't includes any intersects with alive + * vm_struct area, returns 0. + * @buf should be kernel's buffer. Because this function uses KM_USER0, + * the caller should guarantee KM_USER0 is not used. + * + * Note: In usual ops, vread() is never necessary because the caller + * should know vmalloc() area is valid and can use memcpy(). + * This is for routines which have to access vmalloc area without + * any informaion, as /dev/kmem. * - * The caller should guarantee KM_USER1 is not used. */ long vread(char *buf, char *addr, unsigned long count) @@ -1779,8 +1790,9 @@ finished: * @count: number of bytes to be read. * * Returns # of bytes which addr and buf should be incresed. - * (same to count). - * If [addr...addr+count) doesn't includes any valid area, returns 0. + * (same number to @count). + * If [addr...addr+count) doesn't includes any intersect with valid + * vmalloc area, returns 0. * * This function checks that addr is a valid vmalloc'ed area, and * copy data from a buffer to the given addr. If specified range of @@ -1788,6 +1800,11 @@ finished: * proper area of @buf. If there are memory holes, no copy to hole. * IOREMAP area is treated as memory hole and no copy is done. * + * If [addr...addr+count) doesn't includes any intersects with alive + * vm_struct area, returns 0. + * @buf should be kernel's buffer. Because this function uses KM_USER0, + * the caller should guarantee KM_USER0 is not used. + * * Note: In usual ops, vwrite() is never necessary because the caller * should know vmalloc() area is valid and can use memcpy(). * This is for routines which have to access vmalloc area without _ Patches currently in -mm which might be from kamezawa.hiroyu@xxxxxxxxxxxxxx are mm-make-set_mempolicympol_interleav-n_high_memory-aware.patch mm-make-set_mempolicympol_interleav-n_high_memory-aware-fix.patch mm-make-set_mempolicympol_interleav-n_high_memory-aware-fix-2.patch mm-clean-up-page_remove_rmap.patch vmscan-throttle-direct-reclaim-when-too-many-pages-are-isolated-already.patch mm-remove-__addsub_zone_page_state.patch vmscan-dont-attempt-to-reclaim-anon-page-in-lumpy-reclaim-when-no-swap-space-is-avilable.patch ksm-add-mmu_notifier-set_pte_at_notify.patch ksm-first-tidy-up-madvise_vma.patch ksm-define-madv_mergeable-and-madv_unmergeable.patch ksm-the-mm-interface-to-ksm.patch ksm-no-debug-in-page_dup_rmap.patch ksm-identify-pageksm-pages.patch ksm-kernel-samepage-merging.patch ksm-prevent-mremap-move-poisoning.patch ksm-change-copyright-message.patch ksm-change-ksm-nice-level-to-be-5.patch vmalloc-unmap-vmalloc-area-after-hiding-it.patch kcore-fix-vread-vwrite-to-be-aware-of-holes.patch kcore-fix-vread-vwrite-to-be-aware-of-holes-update.patch kcore-proc-kcore-should-use-vread.patch oom-move-oom_adj-to-signal_struct.patch oom-make-oom_score-to-per-process-value.patch oom-oom_kill-doesnt-kill-vfork-parentor-child.patch oom-fix-oom_adjust_write-input-sanity-check.patch oom-fix-oom_adjust_write-input-sanity-check-fix.patch kcore-fix-proc-kcores-statst_size.patch cgroups-support-named-cgroups-hierarchies.patch cgroups-move-the-cgroup-debug-subsys-into-cgroupc-to-access-internal-state.patch cgroups-add-a-back-pointer-from-struct-cg_cgroup_link-to-struct-cgroup.patch cgroups-allow-cgroup-hierarchies-to-be-created-with-no-bound-subsystems.patch memcg-remove-the-overhead-associated-with-the-root-cgroup.patch memcg-remove-the-overhead-associated-with-the-root-cgroup-fix.patch memcg-remove-the-overhead-associated-with-the-root-cgroup-fix-2.patch memcg-add-comments-explaining-memory-barriers.patch memcg-add-comments-explaining-memory-barriers-checkpatch-fixes.patch memory-controller-soft-limit-documentation-v9.patch memory-controller-soft-limit-interface-v9.patch memory-controller-soft-limit-organize-cgroups-v9.patch memory-controller-soft-limit-organize-cgroups-v9-fix.patch memory-controller-soft-limit-refactor-reclaim-flags-v9.patch memory-controller-soft-limit-reclaim-on-contention-v9.patch memory-controller-soft-limit-reclaim-on-contention-v9-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html