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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-24 16:10:23 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-24 16:10:23 -0700
commit9c9fa97a8edbc3668dfc7a25de516e80c146e86f (patch)
tree2dc0e90203796a4b346ce190f9521c3294104058 /kernel
parent5184d449600f501a8688069f35c138c6b3bf8b94 (diff)
parent2b38d01b4de8b1bbda7f5f7e91252609557635fc (diff)
downloadlinux-9c9fa97a8edbc3668dfc7a25de516e80c146e86f.tar.gz
Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton: - a few hot fixes - ocfs2 updates - almost all of -mm (slab-generic, slab, slub, kmemleak, kasan, cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug, sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy, oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap, zsmalloc) * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits) mm/zsmalloc.c: fix a -Wunused-function warning zswap: do not map same object twice zswap: use movable memory if zpool support allocate movable memory zpool: add malloc_support_movable to zpool_driver shmem: fix obsolete comment in shmem_getpage_gfp() mm/madvise: reduce code duplication in error handling paths mm: mmap: increase sockets maximum memory size pgoff for 32bits mm/mmap.c: refine find_vma_prev() with rb_last() riscv: make mmap allocation top-down by default mips: use generic mmap top-down layout and brk randomization mips: replace arch specific way to determine 32bit task with generic version mips: adjust brk randomization offset to fit generic version mips: use STACK_TOP when computing mmap base address mips: properly account for stack randomization and stack guard gap arm: use generic mmap top-down layout and brk randomization arm: use STACK_TOP when computing mmap base address arm: properly account for stack randomization and stack guard gap arm64, mm: make randomization selected by generic topdown mmap layout arm64, mm: move generic mmap layout functions to mm arm64: consider stack randomization for mmap base only when necessary ...
Diffstat (limited to 'kernel')
-rw-r--r--kernel/events/uprobes.c81
-rw-r--r--kernel/resource.c4
-rw-r--r--kernel/sched/idle.c1
-rw-r--r--kernel/sysctl.c6
4 files changed, 68 insertions, 24 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 84fa00497c49..94d38a39d72e 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -26,6 +26,7 @@
#include <linux/percpu-rwsem.h>
#include <linux/task_work.h>
#include <linux/shmem_fs.h>
+#include <linux/khugepaged.h>
#include <linux/uprobes.h>
@@ -143,17 +144,19 @@ static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
*
* @vma: vma that holds the pte pointing to page
* @addr: address the old @page is mapped at
- * @page: the cowed page we are replacing by kpage
- * @kpage: the modified page we replace page by
+ * @old_page: the page we are replacing by new_page
+ * @new_page: the modified page we replace page by
*
- * Returns 0 on success, -EFAULT on failure.
+ * If @new_page is NULL, only unmap @old_page.
+ *
+ * Returns 0 on success, negative error code otherwise.
*/
static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
struct page *old_page, struct page *new_page)
{
struct mm_struct *mm = vma->vm_mm;
struct page_vma_mapped_walk pvmw = {
- .page = old_page,
+ .page = compound_head(old_page),
.vma = vma,
.address = addr,
};
@@ -164,12 +167,12 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, vma, mm, addr,
addr + PAGE_SIZE);
- VM_BUG_ON_PAGE(PageTransHuge(old_page), old_page);
-
- err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL, &memcg,
- false);
- if (err)
- return err;
+ if (new_page) {
+ err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL,
+ &memcg, false);
+ if (err)
+ return err;
+ }
/* For try_to_free_swap() and munlock_vma_page() below */
lock_page(old_page);
@@ -177,15 +180,20 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
mmu_notifier_invalidate_range_start(&range);
err = -EAGAIN;
if (!page_vma_mapped_walk(&pvmw)) {
- mem_cgroup_cancel_charge(new_page, memcg, false);
+ if (new_page)
+ mem_cgroup_cancel_charge(new_page, memcg, false);
goto unlock;
}
VM_BUG_ON_PAGE(addr != pvmw.address, old_page);
- get_page(new_page);
- page_add_new_anon_rmap(new_page, vma, addr, false);
- mem_cgroup_commit_charge(new_page, memcg, false, false);
- lru_cache_add_active_or_unevictable(new_page, vma);
+ if (new_page) {
+ get_page(new_page);
+ page_add_new_anon_rmap(new_page, vma, addr, false);
+ mem_cgroup_commit_charge(new_page, memcg, false, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
+ } else
+ /* no new page, just dec_mm_counter for old_page */
+ dec_mm_counter(mm, MM_ANONPAGES);
if (!PageAnon(old_page)) {
dec_mm_counter(mm, mm_counter_file(old_page));
@@ -194,8 +202,9 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
flush_cache_page(vma, addr, pte_pfn(*pvmw.pte));
ptep_clear_flush_notify(vma, addr, pvmw.pte);
- set_pte_at_notify(mm, addr, pvmw.pte,
- mk_pte(new_page, vma->vm_page_prot));
+ if (new_page)
+ set_pte_at_notify(mm, addr, pvmw.pte,
+ mk_pte(new_page, vma->vm_page_prot));
page_remove_rmap(old_page, false);
if (!page_mapped(old_page))
@@ -464,6 +473,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
struct page *old_page, *new_page;
struct vm_area_struct *vma;
int ret, is_register, ref_ctr_updated = 0;
+ bool orig_page_huge = false;
is_register = is_swbp_insn(&opcode);
uprobe = container_of(auprobe, struct uprobe, arch);
@@ -471,7 +481,7 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
retry:
/* Read the page with vaddr into memory */
ret = get_user_pages_remote(NULL, mm, vaddr, 1,
- FOLL_FORCE | FOLL_SPLIT, &old_page, &vma, NULL);
+ FOLL_FORCE | FOLL_SPLIT_PMD, &old_page, &vma, NULL);
if (ret <= 0)
return ret;
@@ -488,6 +498,10 @@ retry:
ref_ctr_updated = 1;
}
+ ret = 0;
+ if (!is_register && !PageAnon(old_page))
+ goto put_old;
+
ret = anon_vma_prepare(vma);
if (ret)
goto put_old;
@@ -501,8 +515,33 @@ retry:
copy_highpage(new_page, old_page);
copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE);
+ if (!is_register) {
+ struct page *orig_page;
+ pgoff_t index;
+
+ VM_BUG_ON_PAGE(!PageAnon(old_page), old_page);
+
+ index = vaddr_to_offset(vma, vaddr & PAGE_MASK) >> PAGE_SHIFT;
+ orig_page = find_get_page(vma->vm_file->f_inode->i_mapping,
+ index);
+
+ if (orig_page) {
+ if (PageUptodate(orig_page) &&
+ pages_identical(new_page, orig_page)) {
+ /* let go new_page */
+ put_page(new_page);
+ new_page = NULL;
+
+ if (PageCompound(orig_page))
+ orig_page_huge = true;
+ }
+ put_page(orig_page);
+ }
+ }
+
ret = __replace_page(vma, vaddr, old_page, new_page);
- put_page(new_page);
+ if (new_page)
+ put_page(new_page);
put_old:
put_page(old_page);
@@ -513,6 +552,10 @@ put_old:
if (ret && is_register && ref_ctr_updated)
update_ref_ctr(uprobe, mm, -1);
+ /* try collapse pmd for compound page */
+ if (!ret && orig_page_huge)
+ collapse_pte_mapped_thp(mm, vaddr);
+
return ret;
}
diff --git a/kernel/resource.c b/kernel/resource.c
index 74877e9d90ca..76036a41143b 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -487,8 +487,8 @@ int walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
while (start < end &&
!find_next_iomem_res(start, end, flags, IORES_DESC_NONE,
false, &res)) {
- pfn = (res.start + PAGE_SIZE - 1) >> PAGE_SHIFT;
- end_pfn = (res.end + 1) >> PAGE_SHIFT;
+ pfn = PFN_UP(res.start);
+ end_pfn = PFN_DOWN(res.end + 1);
if (end_pfn > pfn)
ret = (*func)(pfn, end_pfn - pfn, arg);
if (ret)
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index c892c6280c9f..8dad5aa600ea 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -238,7 +238,6 @@ static void do_idle(void)
tick_nohz_idle_enter();
while (!need_resched()) {
- check_pgt_cache();
rmb();
local_irq_disable();
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 078950d9605b..00fcea236eba 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -264,7 +264,8 @@ extern struct ctl_table epoll_table[];
extern struct ctl_table firmware_config_table[];
#endif
-#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
+#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
+ defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
int sysctl_legacy_va_layout;
#endif
@@ -1573,7 +1574,8 @@ static struct ctl_table vm_table[] = {
.proc_handler = proc_dointvec,
.extra1 = SYSCTL_ZERO,
},
-#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
+#if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
+ defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
{
.procname = "legacy_va_layout",
.data = &sysctl_legacy_va_layout,