From: Kees Cook <keescook@chromium.org> To: Thomas Gleixner <tglx@linutronix.de> Cc: Kees Cook <keescook@chromium.org>, Peter Zijlstra <peterz@infradead.org>, Elena Reshetova <elena.reshetova@intel.com>, x86@kernel.org, Andy Lutomirski <luto@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Alexander Potapenko <glider@google.com>, Alexander Popov <alex.popov@linux.com>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Jann Horn <jannh@google.com>, kernel-hardening@lists.openwall.com, linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vlastimil Babka <vbabka@suse.cz>, David Hildenbrand <david@redhat.com>, Mike Rapoport <rppt@linux.ibm.com>, Andrew Morton <akpm@linux-foundation.org>, Jonathan Corbet <corbet@lwn.net>, Randy Dunlap <rdunlap@infradead.org> Subject: [PATCH v5 2/7] jump_label: Provide CONFIG-driven build state defaults Date: Tue, 9 Mar 2021 13:42:56 -0800 [thread overview] Message-ID: <20210309214301.678739-3-keescook@chromium.org> (raw) In-Reply-To: <20210309214301.678739-1-keescook@chromium.org> Choosing the initial state of static branches changes the assembly layout (if the condition is expected to be likely, inline, or unlikely, out of line via a jump). A few places in the kernel use (or could be using) a CONFIG to choose the default state, so provide the infrastructure to do this and convert the existing cases (init_on_alloc and init_on_free) to the new macros. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/lkml/20200324220641.GT2452@worktop.programming.kicks-ass.net/ Signed-off-by: Kees Cook <keescook@chromium.org> --- include/linux/jump_label.h | 19 +++++++++++++++++++ include/linux/mm.h | 12 ++---------- mm/page_alloc.c | 12 ++---------- 3 files changed, 23 insertions(+), 20 deletions(-) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index d92691262f51..05f5554d860f 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -382,6 +382,21 @@ struct static_key_false { [0 ... (count) - 1] = STATIC_KEY_FALSE_INIT, \ } +#define _DEFINE_STATIC_KEY_1(name) DEFINE_STATIC_KEY_TRUE(name) +#define _DEFINE_STATIC_KEY_0(name) DEFINE_STATIC_KEY_FALSE(name) +#define DEFINE_STATIC_KEY_MAYBE(cfg, name) \ + __PASTE(_DEFINE_STATIC_KEY_, IS_ENABLED(cfg))(name) + +#define _DEFINE_STATIC_KEY_RO_1(name) DEFINE_STATIC_KEY_TRUE_RO(name) +#define _DEFINE_STATIC_KEY_RO_0(name) DEFINE_STATIC_KEY_FALSE_RO(name) +#define DEFINE_STATIC_KEY_MAYBE_RO(cfg, name) \ + __PASTE(_DEFINE_STATIC_KEY_RO_, IS_ENABLED(cfg))(name) + +#define _DECLARE_STATIC_KEY_1(name) DECLARE_STATIC_KEY_TRUE(name) +#define _DECLARE_STATIC_KEY_0(name) DECLARE_STATIC_KEY_FALSE(name) +#define DECLARE_STATIC_KEY_MAYBE(cfg, name) \ + __PASTE(_DECLARE_STATIC_KEY_, IS_ENABLED(cfg))(name) + extern bool ____wrong_branch_error(void); #define static_key_enabled(x) \ @@ -482,6 +497,10 @@ extern bool ____wrong_branch_error(void); #endif /* CONFIG_JUMP_LABEL */ +#define static_branch_maybe(config, x) \ + (IS_ENABLED(config) ? static_branch_likely(x) \ + : static_branch_unlikely(x)) + /* * Advanced usage; refcount, branch is enabled when: count != 0 */ diff --git a/include/linux/mm.h b/include/linux/mm.h index b3317d91ee8e..bf341a9bfe46 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2871,11 +2871,7 @@ static inline void kernel_poison_pages(struct page *page, int numpages) { } static inline void kernel_unpoison_pages(struct page *page, int numpages) { } #endif -#ifdef CONFIG_INIT_ON_ALLOC_DEFAULT_ON -DECLARE_STATIC_KEY_TRUE(init_on_alloc); -#else -DECLARE_STATIC_KEY_FALSE(init_on_alloc); -#endif +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); static inline bool want_init_on_alloc(gfp_t flags) { if (static_branch_unlikely(&init_on_alloc)) @@ -2883,11 +2879,7 @@ static inline bool want_init_on_alloc(gfp_t flags) return flags & __GFP_ZERO; } -#ifdef CONFIG_INIT_ON_FREE_DEFAULT_ON -DECLARE_STATIC_KEY_TRUE(init_on_free); -#else -DECLARE_STATIC_KEY_FALSE(init_on_free); -#endif +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); static inline bool want_init_on_free(void) { return static_branch_unlikely(&init_on_free); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f2d474a844cf..267c04b8911d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -167,18 +167,10 @@ unsigned long totalcma_pages __read_mostly; int percpu_pagelist_fraction; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; -#ifdef CONFIG_INIT_ON_ALLOC_DEFAULT_ON -DEFINE_STATIC_KEY_TRUE(init_on_alloc); -#else -DEFINE_STATIC_KEY_FALSE(init_on_alloc); -#endif +DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); EXPORT_SYMBOL(init_on_alloc); -#ifdef CONFIG_INIT_ON_FREE_DEFAULT_ON -DEFINE_STATIC_KEY_TRUE(init_on_free); -#else -DEFINE_STATIC_KEY_FALSE(init_on_free); -#endif +DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); EXPORT_SYMBOL(init_on_free); static bool _init_on_alloc_enabled_early __read_mostly -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org> To: Thomas Gleixner <tglx@linutronix.de> Cc: Kees Cook <keescook@chromium.org>, Peter Zijlstra <peterz@infradead.org>, Elena Reshetova <elena.reshetova@intel.com>, x86@kernel.org, Andy Lutomirski <luto@kernel.org>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Alexander Potapenko <glider@google.com>, Alexander Popov <alex.popov@linux.com>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Jann Horn <jannh@google.com>, kernel-hardening@lists.openwall.com, linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Vlastimil Babka <vbabka@suse.cz>, David Hildenbrand <david@redhat.com>, Mike Rapoport <rppt@linux.ibm.com>, Andrew Morton <akpm@linux-foundation.org>, Jonathan Corbet <corbet@lwn.net>, Randy Dunlap <rdunlap@infradead.org> Subject: [PATCH v5 2/7] jump_label: Provide CONFIG-driven build state defaults Date: Tue, 9 Mar 2021 13:42:56 -0800 [thread overview] Message-ID: <20210309214301.678739-3-keescook@chromium.org> (raw) In-Reply-To: <20210309214301.678739-1-keescook@chromium.org> Choosing the initial state of static branches changes the assembly layout (if the condition is expected to be likely, inline, or unlikely, out of line via a jump). A few places in the kernel use (or could be using) a CONFIG to choose the default state, so provide the infrastructure to do this and convert the existing cases (init_on_alloc and init_on_free) to the new macros. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/lkml/20200324220641.GT2452@worktop.programming.kicks-ass.net/ Signed-off-by: Kees Cook <keescook@chromium.org> --- include/linux/jump_label.h | 19 +++++++++++++++++++ include/linux/mm.h | 12 ++---------- mm/page_alloc.c | 12 ++---------- 3 files changed, 23 insertions(+), 20 deletions(-) diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index d92691262f51..05f5554d860f 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -382,6 +382,21 @@ struct static_key_false { [0 ... (count) - 1] = STATIC_KEY_FALSE_INIT, \ } +#define _DEFINE_STATIC_KEY_1(name) DEFINE_STATIC_KEY_TRUE(name) +#define _DEFINE_STATIC_KEY_0(name) DEFINE_STATIC_KEY_FALSE(name) +#define DEFINE_STATIC_KEY_MAYBE(cfg, name) \ + __PASTE(_DEFINE_STATIC_KEY_, IS_ENABLED(cfg))(name) + +#define _DEFINE_STATIC_KEY_RO_1(name) DEFINE_STATIC_KEY_TRUE_RO(name) +#define _DEFINE_STATIC_KEY_RO_0(name) DEFINE_STATIC_KEY_FALSE_RO(name) +#define DEFINE_STATIC_KEY_MAYBE_RO(cfg, name) \ + __PASTE(_DEFINE_STATIC_KEY_RO_, IS_ENABLED(cfg))(name) + +#define _DECLARE_STATIC_KEY_1(name) DECLARE_STATIC_KEY_TRUE(name) +#define _DECLARE_STATIC_KEY_0(name) DECLARE_STATIC_KEY_FALSE(name) +#define DECLARE_STATIC_KEY_MAYBE(cfg, name) \ + __PASTE(_DECLARE_STATIC_KEY_, IS_ENABLED(cfg))(name) + extern bool ____wrong_branch_error(void); #define static_key_enabled(x) \ @@ -482,6 +497,10 @@ extern bool ____wrong_branch_error(void); #endif /* CONFIG_JUMP_LABEL */ +#define static_branch_maybe(config, x) \ + (IS_ENABLED(config) ? static_branch_likely(x) \ + : static_branch_unlikely(x)) + /* * Advanced usage; refcount, branch is enabled when: count != 0 */ diff --git a/include/linux/mm.h b/include/linux/mm.h index b3317d91ee8e..bf341a9bfe46 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2871,11 +2871,7 @@ static inline void kernel_poison_pages(struct page *page, int numpages) { } static inline void kernel_unpoison_pages(struct page *page, int numpages) { } #endif -#ifdef CONFIG_INIT_ON_ALLOC_DEFAULT_ON -DECLARE_STATIC_KEY_TRUE(init_on_alloc); -#else -DECLARE_STATIC_KEY_FALSE(init_on_alloc); -#endif +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); static inline bool want_init_on_alloc(gfp_t flags) { if (static_branch_unlikely(&init_on_alloc)) @@ -2883,11 +2879,7 @@ static inline bool want_init_on_alloc(gfp_t flags) return flags & __GFP_ZERO; } -#ifdef CONFIG_INIT_ON_FREE_DEFAULT_ON -DECLARE_STATIC_KEY_TRUE(init_on_free); -#else -DECLARE_STATIC_KEY_FALSE(init_on_free); -#endif +DECLARE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); static inline bool want_init_on_free(void) { return static_branch_unlikely(&init_on_free); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index f2d474a844cf..267c04b8911d 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -167,18 +167,10 @@ unsigned long totalcma_pages __read_mostly; int percpu_pagelist_fraction; gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; -#ifdef CONFIG_INIT_ON_ALLOC_DEFAULT_ON -DEFINE_STATIC_KEY_TRUE(init_on_alloc); -#else -DEFINE_STATIC_KEY_FALSE(init_on_alloc); -#endif +DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_ALLOC_DEFAULT_ON, init_on_alloc); EXPORT_SYMBOL(init_on_alloc); -#ifdef CONFIG_INIT_ON_FREE_DEFAULT_ON -DEFINE_STATIC_KEY_TRUE(init_on_free); -#else -DEFINE_STATIC_KEY_FALSE(init_on_free); -#endif +DEFINE_STATIC_KEY_MAYBE(CONFIG_INIT_ON_FREE_DEFAULT_ON, init_on_free); EXPORT_SYMBOL(init_on_free); static bool _init_on_alloc_enabled_early __read_mostly -- 2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-03-09 21:44 UTC|newest] Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-03-09 21:42 [PATCH v5 0/7] Optionally randomize kernel stack offset each syscall Kees Cook 2021-03-09 21:42 ` Kees Cook 2021-03-09 21:42 ` [PATCH v5 1/7] mm: Restore init_on_* static branch defaults Kees Cook 2021-03-09 21:42 ` Kees Cook 2021-03-10 23:56 ` Andrew Morton 2021-03-10 23:56 ` Andrew Morton 2021-03-15 17:28 ` Kees Cook 2021-03-15 17:28 ` Kees Cook 2021-03-09 21:42 ` Kees Cook [this message] 2021-03-09 21:42 ` [PATCH v5 2/7] jump_label: Provide CONFIG-driven build state defaults Kees Cook 2021-03-09 21:42 ` [PATCH v5 3/7] init_on_alloc: Unpessimize default-on builds Kees Cook 2021-03-09 21:42 ` Kees Cook 2021-03-10 12:52 ` Andrey Konovalov 2021-03-10 12:52 ` Andrey Konovalov 2021-03-10 12:52 ` Andrey Konovalov 2021-03-10 21:03 ` Kees Cook 2021-03-10 21:03 ` Kees Cook 2021-03-09 21:42 ` [PATCH v5 4/7] stack: Optionally randomize kernel stack offset each syscall Kees Cook 2021-03-09 21:42 ` Kees Cook 2021-03-09 21:42 ` [PATCH v5 5/7] x86/entry: Enable random_kstack_offset support Kees Cook 2021-03-09 21:42 ` Kees Cook 2021-03-09 21:43 ` [PATCH v5 6/7] arm64: entry: " Kees Cook 2021-03-09 21:43 ` Kees Cook 2021-03-09 21:43 ` [PATCH v5 7/7] lkdtm: Add REPORT_STACK for checking stack offsets Kees Cook 2021-03-09 21:43 ` Kees Cook
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