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 PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 6 Oct 2015 18:23:58 +0300 From: "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com> To: Andrew Morton <akpm@...ux-foundation.org>, Andrea Arcangeli <aarcange@...hat.com>, Hugh Dickins <hughd@...gle.com> Cc: Dave Hansen <dave.hansen@...el.com>, Mel Gorman <mgorman@...e.de>, Rik van Riel <riel@...hat.com>, Vlastimil Babka <vbabka@...e.cz>, Christoph Lameter <cl@...two.org>, Naoya Horiguchi <n-horiguchi@...jp.nec.com>, Steve Capper <steve.capper@...aro.org>, "Aneesh Kumar K.V" <aneesh.kumar@...ux.vnet.ibm.com>, Johannes Weiner <hannes@...xchg.org>, Michal Hocko <mhocko@...e.cz>, Jerome Marchand <jmarchan@...hat.com>, Sasha Levin <sasha.levin@...cle.com>, linux-kernel@...r.kernel.org, linux-mm@...ck.org, "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com> Subject: [PATCHv12 31/37] thp, mm: split_huge_page(): caller need to lock page We're going to use migration entries instead of compound_lock() to stabilize page refcounts. Setup and remove migration entries require page to be locked. Some of split_huge_page() callers already have the page locked. Let's require everybody to lock the page before calling split_huge_page(). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com> Tested-by: Sasha Levin <sasha.levin@...cle.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@...ux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@...e.cz> Acked-by: Jerome Marchand <jmarchan@...hat.com> --- mm/memory-failure.c | 8 +++++++- mm/migrate.c | 8 ++++++-- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5b965e27aaae..a2c987df80eb 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1149,7 +1149,9 @@ int memory_failure(unsigned long pfn, int trapno, int flags) } if (!PageHuge(p) && PageTransHuge(hpage)) { + lock_page(hpage); if (!PageAnon(hpage) || unlikely(split_huge_page(hpage))) { + unlock_page(hpage); if (!PageAnon(hpage)) pr_err("MCE: %#lx: non anonymous thp\n", pfn); else @@ -1159,6 +1161,7 @@ int memory_failure(unsigned long pfn, int trapno, int flags) put_hwpoison_page(p); return -EBUSY; } + unlock_page(hpage); VM_BUG_ON_PAGE(!page_count(p), p); hpage = compound_head(p); } @@ -1751,7 +1754,10 @@ int soft_offline_page(struct page *page, int flags) return -EBUSY; } if (!PageHuge(page) && PageTransHuge(hpage)) { - if (PageAnon(hpage) && unlikely(split_huge_page(hpage))) { + lock_page(page); + ret = split_huge_page(hpage); + unlock_page(page); + if (unlikely(ret)) { pr_info("soft offline: %#lx: failed to split THP\n", pfn); if (flags & MF_COUNT_INCREASED) diff --git a/mm/migrate.c b/mm/migrate.c index 45fadab47c53..c58bc6824d66 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -949,9 +949,13 @@ static ICE_noinline int unmap_and_move(new_page_t get_new_page, goto out; } - if (unlikely(PageTransHuge(page))) - if (unlikely(split_huge_page(page))) + if (unlikely(PageTransHuge(page))) { + lock_page(page); + rc = split_huge_page(page); + unlock_page(page); + if (rc) goto out; + } rc = __unmap_and_move(page, newpage, force, mode); -- 2.5.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists