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From: Rick Edgecombe <rick.p.edgecombe@intel.com>
To: Andy Lutomirski <luto@kernel.org>, Ingo Molnar <mingo@redhat.com>
Cc: linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com,
	Thomas Gleixner <tglx@linutronix.de>,
	Borislav Petkov <bp@alien8.de>, Nadav Amit <nadav.amit@gmail.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Peter Zijlstra <peterz@infradead.org>,
	linux_dti@icloud.com, linux-integrity@vger.kernel.org,
	linux-security-module@vger.kernel.org, akpm@linux-foundation.org,
	kernel-hardening@lists.openwall.com, linux-mm@kvack.org,
	will.deacon@arm.com, ard.biesheuvel@linaro.org,
	kristen@linux.intel.com, deneen.t.dock@intel.com,
	Rick Edgecombe <rick.p.edgecombe@intel.com>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Pavel Machek <pavel@ucw.cz>
Subject: [PATCH v2 14/20] mm: Make hibernate handle unmapped pages
Date: Mon, 28 Jan 2019 16:34:16 -0800	[thread overview]
Message-ID: <20190129003422.9328-15-rick.p.edgecombe@intel.com> (raw)
In-Reply-To: <20190129003422.9328-1-rick.p.edgecombe@intel.com>

For architectures with CONFIG_ARCH_HAS_SET_ALIAS, pages can be unmapped
briefly on the directmap, even when CONFIG_DEBUG_PAGEALLOC is not
configured. So this changes kernel_map_pages and kernel_page_present to be
defined when CONFIG_ARCH_HAS_SET_ALIAS is defined as well. It also changes
places (page_alloc.c) where those functions are assumed to only be
implemented when CONFIG_DEBUG_PAGEALLOC is defined.

So now when CONFIG_ARCH_HAS_SET_ALIAS=y, hibernate will handle not present
page when saving. Previously this was already done when
CONFIG_DEBUG_PAGEALLOC was configured. It does not appear to have a big
hibernating performance impact.

Before:
[    4.670938] PM: Wrote 171996 kbytes in 0.21 seconds (819.02 MB/s)

After:
[    4.504714] PM: Wrote 178932 kbytes in 0.22 seconds (813.32 MB/s)

Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Pavel Machek <pavel@ucw.cz>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
---
 arch/x86/mm/pageattr.c |  4 ----
 include/linux/mm.h     | 18 ++++++------------
 mm/page_alloc.c        |  7 +++++--
 3 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 3a51915a1410..717bdc188aab 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -2257,7 +2257,6 @@ int set_alias_default_noflush(struct page *page)
 	return __set_pages_p(page, 1);
 }
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
 void __kernel_map_pages(struct page *page, int numpages, int enable)
 {
 	if (PageHighMem(page))
@@ -2302,11 +2301,8 @@ bool kernel_page_present(struct page *page)
 	pte = lookup_address((unsigned long)page_address(page), &level);
 	return (pte_val(*pte) & _PAGE_PRESENT);
 }
-
 #endif /* CONFIG_HIBERNATION */
 
-#endif /* CONFIG_DEBUG_PAGEALLOC */
-
 int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
 				   unsigned numpages, unsigned long page_flags)
 {
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 80bb6408fe73..b362a280a919 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -2642,37 +2642,31 @@ static inline void kernel_poison_pages(struct page *page, int numpages,
 					int enable) { }
 #endif
 
-#ifdef CONFIG_DEBUG_PAGEALLOC
 extern bool _debug_pagealloc_enabled;
-extern void __kernel_map_pages(struct page *page, int numpages, int enable);
 
 static inline bool debug_pagealloc_enabled(void)
 {
-	return _debug_pagealloc_enabled;
+	return IS_ENABLED(CONFIG_DEBUG_PAGEALLOC) && _debug_pagealloc_enabled;
 }
 
+#if defined(CONFIG_DEBUG_PAGEALLOC) || defined(CONFIG_ARCH_HAS_SET_ALIAS)
+extern void __kernel_map_pages(struct page *page, int numpages, int enable);
+
 static inline void
 kernel_map_pages(struct page *page, int numpages, int enable)
 {
-	if (!debug_pagealloc_enabled())
-		return;
-
 	__kernel_map_pages(page, numpages, enable);
 }
 #ifdef CONFIG_HIBERNATION
 extern bool kernel_page_present(struct page *page);
 #endif	/* CONFIG_HIBERNATION */
-#else	/* CONFIG_DEBUG_PAGEALLOC */
+#else	/* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_ALIAS */
 static inline void
 kernel_map_pages(struct page *page, int numpages, int enable) {}
 #ifdef CONFIG_HIBERNATION
 static inline bool kernel_page_present(struct page *page) { return true; }
 #endif	/* CONFIG_HIBERNATION */
-static inline bool debug_pagealloc_enabled(void)
-{
-	return false;
-}
-#endif	/* CONFIG_DEBUG_PAGEALLOC */
+#endif	/* CONFIG_DEBUG_PAGEALLOC || CONFIG_ARCH_HAS_SET_ALIAS */
 
 #ifdef __HAVE_ARCH_GATE_AREA
 extern struct vm_area_struct *get_gate_vma(struct mm_struct *mm);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d295c9bc01a8..92d0a0934274 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1074,7 +1074,9 @@ static __always_inline bool free_pages_prepare(struct page *page,
 	}
 	arch_free_page(page, order);
 	kernel_poison_pages(page, 1 << order, 0);
-	kernel_map_pages(page, 1 << order, 0);
+	if (debug_pagealloc_enabled())
+		kernel_map_pages(page, 1 << order, 0);
+
 	kasan_free_nondeferred_pages(page, order);
 
 	return true;
@@ -1944,7 +1946,8 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
 	set_page_refcounted(page);
 
 	arch_alloc_page(page, order);
-	kernel_map_pages(page, 1 << order, 1);
+	if (debug_pagealloc_enabled())
+		kernel_map_pages(page, 1 << order, 1);
 	kernel_poison_pages(page, 1 << order, 1);
 	kasan_alloc_pages(page, order);
 	set_page_owner(page, order, gfp_flags);
-- 
2.17.1

  parent reply	other threads:[~2019-01-29  0:34 UTC|newest]

Thread overview: 71+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-01-29  0:34 [PATCH v2 00/20] Merge text_poke fixes and executable lockdowns Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 01/20] Fix "x86/alternatives: Lockdep-enforce text_mutex in text_poke*()" Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 02/20] x86/jump_label: Use text_poke_early() during early init Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 03/20] x86/mm: temporary mm struct Rick Edgecombe
2019-01-31 11:29   ` Borislav Petkov
2019-01-31 22:19     ` Nadav Amit
2019-02-01  0:08       ` Borislav Petkov
2019-02-01  0:25         ` Nadav Amit
2019-02-04 14:28       ` Borislav Petkov
2019-01-29  0:34 ` [PATCH v2 04/20] fork: provide a function for copying init_mm Rick Edgecombe
2019-02-05  8:53   ` Borislav Petkov
2019-02-05  9:03     ` Nadav Amit
2019-01-29  0:34 ` [PATCH v2 05/20] x86/alternative: initializing temporary mm for patching Rick Edgecombe
2019-02-05  9:18   ` Borislav Petkov
2019-02-11  0:39   ` Nadav Amit
2019-02-11  5:18     ` Andy Lutomirski
2019-02-11 18:04       ` Nadav Amit
2019-02-11 19:07         ` Andy Lutomirski
2019-02-11 19:18           ` Nadav Amit
2019-02-11 22:47             ` Andy Lutomirski
2019-02-12 18:23               ` Nadav Amit
2019-01-29  0:34 ` [PATCH v2 06/20] x86/alternative: use temporary mm for text poking Rick Edgecombe
2019-02-05  9:58   ` Borislav Petkov
2019-02-05 11:31     ` Peter Zijlstra
2019-02-05 12:35       ` Borislav Petkov
2019-02-05 13:25         ` Peter Zijlstra
2019-02-05 17:54         ` Nadav Amit
2019-02-05 13:29       ` Peter Zijlstra
2019-01-29  0:34 ` [PATCH v2 07/20] x86/kgdb: avoid redundant comparison of patched code Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 08/20] x86/ftrace: set trampoline pages as executable Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 09/20] x86/kprobes: instruction pages initialization enhancements Rick Edgecombe
2019-02-11 18:22   ` Borislav Petkov
2019-02-11 19:36     ` Nadav Amit
2019-01-29  0:34 ` [PATCH v2 10/20] x86: avoid W^X being broken during modules loading Rick Edgecombe
2019-02-11 18:29   ` Borislav Petkov
2019-02-11 18:45     ` Nadav Amit
2019-02-11 19:01       ` Borislav Petkov
2019-02-11 19:09         ` Nadav Amit
2019-02-11 19:10           ` Borislav Petkov
2019-02-11 19:27             ` Nadav Amit
2019-02-11 19:42               ` Borislav Petkov
2019-02-11 20:32                 ` Nadav Amit
2019-03-07 15:10                   ` [PATCH] x86/cpufeature: Remove __pure attribute to _static_cpu_has() Borislav Petkov
2019-03-07 16:43                     ` hpa
2019-03-07 17:02                       ` Borislav Petkov
2019-03-07  7:29                 ` [PATCH v2 10/20] x86: avoid W^X being broken during modules loading Borislav Petkov
2019-03-07 16:53                   ` hpa
2019-03-07 17:06                     ` Borislav Petkov
2019-03-07 20:02                       ` Andy Lutomirski
2019-03-07 20:25                         ` Borislav Petkov
2019-01-29  0:34 ` [PATCH v2 11/20] x86/jump-label: remove support for custom poker Rick Edgecombe
2019-02-11 18:37   ` Borislav Petkov
2019-01-29  0:34 ` [PATCH v2 12/20] x86/alternative: Remove the return value of text_poke_*() Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 13/20] Add set_alias_ function and x86 implementation Rick Edgecombe
2019-02-11 19:09   ` Borislav Petkov
2019-02-11 19:27     ` Edgecombe, Rick P
2019-02-11 22:59     ` Andy Lutomirski
2019-02-12  0:01       ` Edgecombe, Rick P
2019-01-29  0:34 ` Rick Edgecombe [this message]
2019-02-19 11:04   ` [PATCH v2 14/20] mm: Make hibernate handle unmapped pages Borislav Petkov
2019-02-19 21:28     ` Edgecombe, Rick P
2019-02-20 16:07       ` Borislav Petkov
2019-01-29  0:34 ` [PATCH v2 15/20] vmalloc: New flags for safe vfree on special perms Rick Edgecombe
2019-02-19 12:48   ` Borislav Petkov
2019-02-19 19:42     ` Edgecombe, Rick P
2019-02-20 16:14       ` Borislav Petkov
2019-01-29  0:34 ` [PATCH v2 16/20] modules: Use vmalloc special flag Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 17/20] bpf: " Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 18/20] x86/ftrace: " Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 19/20] x86/kprobes: " Rick Edgecombe
2019-01-29  0:34 ` [PATCH v2 20/20] x86/alternative: comment about module removal races Rick Edgecombe

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