From f0cd34061300dc501ace5261cb527a6deabe1000 Mon Sep 17 00:00:00 2001 From: Dou Liyang Date: Wed, 6 Sep 2017 16:18:32 -0700 Subject: metag/numa: remove the unused parent_node() macro Commit a7be6e5a7f8d ("mm: drop useless local parameters of __register_one_node()") removes the last user of parent_node(). The parent_node() macro in METAG architecture is unnecessary. Remove it for cleanup. Link: http://lkml.kernel.org/r/1501076076-1974-4-git-send-email-douly.fnst@cn.fujitsu.com Signed-off-by: Dou Liyang Reported-by: Michael Ellerman Cc: James Hogan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/metag/include/asm/topology.h | 1 - 1 file changed, 1 deletion(-) (limited to 'arch') diff --git a/arch/metag/include/asm/topology.h b/arch/metag/include/asm/topology.h index e95f874ded1b..707c7f7b6bea 100644 --- a/arch/metag/include/asm/topology.h +++ b/arch/metag/include/asm/topology.h @@ -4,7 +4,6 @@ #ifdef CONFIG_NUMA #define cpu_to_node(cpu) ((void)(cpu), 0) -#define parent_node(node) ((void)(node), 0) #define cpumask_of_node(node) ((void)node, cpu_online_mask) -- cgit v1.2.3 From aafd4562dfee81a40ba21b5ea3cf5e06664bc7f6 Mon Sep 17 00:00:00 2001 From: Mike Kravetz Date: Wed, 6 Sep 2017 16:23:29 -0700 Subject: mm: arch: consolidate mmap hugetlb size encodings A non-default huge page size can be encoded in the flags argument of the mmap system call. The definitions for these encodings are in arch specific header files. However, all architectures use the same values. Consolidate all the definitions in the primary user header file (uapi/linux/mman.h). Include definitions for all known huge page sizes. Use the generic encoding definitions in hugetlb_encode.h as the basis for these definitions. Link: http://lkml.kernel.org/r/1501527386-10736-3-git-send-email-mike.kravetz@oracle.com Signed-off-by: Mike Kravetz Acked-by: Michal Hocko Cc: Andi Kleen Cc: Andrea Arcangeli Cc: Aneesh Kumar K.V Cc: Anshuman Khandual Cc: Arnd Bergmann Cc: Davidlohr Bueso Cc: Matthew Wilcox Cc: Michael Kerrisk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/include/uapi/asm/mman.h | 11 ----------- arch/mips/include/uapi/asm/mman.h | 11 ----------- arch/parisc/include/uapi/asm/mman.h | 11 ----------- arch/powerpc/include/uapi/asm/mman.h | 16 ---------------- arch/x86/include/uapi/asm/mman.h | 3 --- arch/xtensa/include/uapi/asm/mman.h | 11 ----------- 6 files changed, 63 deletions(-) (limited to 'arch') diff --git a/arch/alpha/include/uapi/asm/mman.h b/arch/alpha/include/uapi/asm/mman.h index 02760f6e6ca4..13b52aad3c43 100644 --- a/arch/alpha/include/uapi/asm/mman.h +++ b/arch/alpha/include/uapi/asm/mman.h @@ -67,17 +67,6 @@ /* compatibility flags */ #define MAP_FILE 0 -/* - * When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size. - * This gives us 6 bits, which is enough until someone invents 128 bit address - * spaces. - * - * Assume these are all power of twos. - * When 0 use the default page size. - */ -#define MAP_HUGE_SHIFT 26 -#define MAP_HUGE_MASK 0x3f - #define PKEY_DISABLE_ACCESS 0x1 #define PKEY_DISABLE_WRITE 0x2 #define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\ diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h index 655e2fb5395b..398eebcc3541 100644 --- a/arch/mips/include/uapi/asm/mman.h +++ b/arch/mips/include/uapi/asm/mman.h @@ -94,17 +94,6 @@ /* compatibility flags */ #define MAP_FILE 0 -/* - * When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size. - * This gives us 6 bits, which is enough until someone invents 128 bit address - * spaces. - * - * Assume these are all power of twos. - * When 0 use the default page size. - */ -#define MAP_HUGE_SHIFT 26 -#define MAP_HUGE_MASK 0x3f - #define PKEY_DISABLE_ACCESS 0x1 #define PKEY_DISABLE_WRITE 0x2 #define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\ diff --git a/arch/parisc/include/uapi/asm/mman.h b/arch/parisc/include/uapi/asm/mman.h index 9a9c2fe4be50..b87fbe3f338a 100644 --- a/arch/parisc/include/uapi/asm/mman.h +++ b/arch/parisc/include/uapi/asm/mman.h @@ -64,17 +64,6 @@ #define MAP_FILE 0 #define MAP_VARIABLE 0 -/* - * When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size. - * This gives us 6 bits, which is enough until someone invents 128 bit address - * spaces. - * - * Assume these are all power of twos. - * When 0 use the default page size. - */ -#define MAP_HUGE_SHIFT 26 -#define MAP_HUGE_MASK 0x3f - #define PKEY_DISABLE_ACCESS 0x1 #define PKEY_DISABLE_WRITE 0x2 #define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\ diff --git a/arch/powerpc/include/uapi/asm/mman.h b/arch/powerpc/include/uapi/asm/mman.h index ab45cc2f3101..03c06ba7464f 100644 --- a/arch/powerpc/include/uapi/asm/mman.h +++ b/arch/powerpc/include/uapi/asm/mman.h @@ -29,20 +29,4 @@ #define MAP_STACK 0x20000 /* give out an address that is best suited for process/thread stacks */ #define MAP_HUGETLB 0x40000 /* create a huge page mapping */ -/* - * When MAP_HUGETLB is set, bits [26:31] of the flags argument to mmap(2), - * encode the log2 of the huge page size. A value of zero indicates that the - * default huge page size should be used. To use a non-default huge page size, - * one of these defines can be used, or the size can be encoded by hand. Note - * that on most systems only a subset, or possibly none, of these sizes will be - * available. - */ -#define MAP_HUGE_512KB (19 << MAP_HUGE_SHIFT) /* 512KB HugeTLB Page */ -#define MAP_HUGE_1MB (20 << MAP_HUGE_SHIFT) /* 1MB HugeTLB Page */ -#define MAP_HUGE_2MB (21 << MAP_HUGE_SHIFT) /* 2MB HugeTLB Page */ -#define MAP_HUGE_8MB (23 << MAP_HUGE_SHIFT) /* 8MB HugeTLB Page */ -#define MAP_HUGE_16MB (24 << MAP_HUGE_SHIFT) /* 16MB HugeTLB Page */ -#define MAP_HUGE_1GB (30 << MAP_HUGE_SHIFT) /* 1GB HugeTLB Page */ -#define MAP_HUGE_16GB (34 << MAP_HUGE_SHIFT) /* 16GB HugeTLB Page */ - #endif /* _UAPI_ASM_POWERPC_MMAN_H */ diff --git a/arch/x86/include/uapi/asm/mman.h b/arch/x86/include/uapi/asm/mman.h index 39bca7fac087..3be08f07695c 100644 --- a/arch/x86/include/uapi/asm/mman.h +++ b/arch/x86/include/uapi/asm/mman.h @@ -3,9 +3,6 @@ #define MAP_32BIT 0x40 /* only give out 32bit addresses */ -#define MAP_HUGE_2MB (21 << MAP_HUGE_SHIFT) -#define MAP_HUGE_1GB (30 << MAP_HUGE_SHIFT) - #ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS /* * Take the 4 protection key bits out of the vma->vm_flags diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h index 24365b30aae9..8ce77a2e9bab 100644 --- a/arch/xtensa/include/uapi/asm/mman.h +++ b/arch/xtensa/include/uapi/asm/mman.h @@ -106,17 +106,6 @@ /* compatibility flags */ #define MAP_FILE 0 -/* - * When MAP_HUGETLB is set bits [26:31] encode the log2 of the huge page size. - * This gives us 6 bits, which is enough until someone invents 128 bit address - * spaces. - * - * Assume these are all power of twos. - * When 0 use the default page size. - */ -#define MAP_HUGE_SHIFT 26 -#define MAP_HUGE_MASK 0x3f - #define PKEY_DISABLE_ACCESS 0x1 #define PKEY_DISABLE_WRITE 0x2 #define PKEY_ACCESS_MASK (PKEY_DISABLE_ACCESS |\ -- cgit v1.2.3 From df3735c5b40fad8d0d28eb8ab065fe955b3347ee Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Wed, 6 Sep 2017 16:25:11 -0700 Subject: x86,mpx: make mpx depend on x86-64 to free up VMA flag MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "mm,fork,security: introduce MADV_WIPEONFORK", v4. If a child process accesses memory that was MADV_WIPEONFORK, it will get zeroes. The address ranges are still valid, they are just empty. If a child process accesses memory that was MADV_DONTFORK, it will get a segmentation fault, since those address ranges are no longer valid in the child after fork. Since MADV_DONTFORK also seems to be used to allow very large programs to fork in systems with strict memory overcommit restrictions, changing the semantics of MADV_DONTFORK might break existing programs. The use case is libraries that store or cache information, and want to know that they need to regenerate it in the child process after fork. Examples of this would be: - systemd/pulseaudio API checks (fail after fork) (replacing a getpid check, which is too slow without a PID cache) - PKCS#11 API reinitialization check (mandated by specification) - glibc's upcoming PRNG (reseed after fork) - OpenSSL PRNG (reseed after fork) The security benefits of a forking server having a re-inialized PRNG in every child process are pretty obvious. However, due to libraries having all kinds of internal state, and programs getting compiled with many different versions of each library, it is unreasonable to expect calling programs to re-initialize everything manually after fork. A further complication is the proliferation of clone flags, programs bypassing glibc's functions to call clone directly, and programs calling unshare, causing the glibc pthread_atfork hook to not get called. It would be better to have the kernel take care of this automatically. The patchset also adds MADV_KEEPONFORK, to undo the effects of a prior MADV_WIPEONFORK. This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO: https://man.openbsd.org/minherit.2 This patch (of 2): MPX only seems to be available on 64 bit CPUs, starting with Skylake and Goldmont. Move VM_MPX into the 64 bit only portion of vma->vm_flags, in order to free up a VMA flag. Link: http://lkml.kernel.org/r/20170811212829.29186-2-riel@redhat.com Signed-off-by: Rik van Riel Acked-by: Dave Hansen Cc: Mike Kravetz Cc: Florian Weimer Cc: Kees Cook Cc: Andy Lutomirski Cc: Will Drewry Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: "Kirill A. Shutemov" Cc: Matthew Wilcox Cc: Colm MacCártaigh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86/Kconfig | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index acb366bf6bc1..4b278a33ccbb 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1806,7 +1806,9 @@ config X86_SMAP config X86_INTEL_MPX prompt "Intel MPX (Memory Protection Extensions)" def_bool n - depends on CPU_SUP_INTEL + # Note: only available in 64-bit mode due to VMA flags shortage + depends on CPU_SUP_INTEL && X86_64 + select ARCH_USES_HIGH_VMA_FLAGS ---help--- MPX provides hardware features that can be used in conjunction with compiler-instrumented code to check -- cgit v1.2.3 From d2cd9ede6e193dd7d88b6d27399e96229a551b19 Mon Sep 17 00:00:00 2001 From: Rik van Riel Date: Wed, 6 Sep 2017 16:25:15 -0700 Subject: mm,fork: introduce MADV_WIPEONFORK MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce MADV_WIPEONFORK semantics, which result in a VMA being empty in the child process after fork. This differs from MADV_DONTFORK in one important way. If a child process accesses memory that was MADV_WIPEONFORK, it will get zeroes. The address ranges are still valid, they are just empty. If a child process accesses memory that was MADV_DONTFORK, it will get a segmentation fault, since those address ranges are no longer valid in the child after fork. Since MADV_DONTFORK also seems to be used to allow very large programs to fork in systems with strict memory overcommit restrictions, changing the semantics of MADV_DONTFORK might break existing programs. MADV_WIPEONFORK only works on private, anonymous VMAs. The use case is libraries that store or cache information, and want to know that they need to regenerate it in the child process after fork. Examples of this would be: - systemd/pulseaudio API checks (fail after fork) (replacing a getpid check, which is too slow without a PID cache) - PKCS#11 API reinitialization check (mandated by specification) - glibc's upcoming PRNG (reseed after fork) - OpenSSL PRNG (reseed after fork) The security benefits of a forking server having a re-inialized PRNG in every child process are pretty obvious. However, due to libraries having all kinds of internal state, and programs getting compiled with many different versions of each library, it is unreasonable to expect calling programs to re-initialize everything manually after fork. A further complication is the proliferation of clone flags, programs bypassing glibc's functions to call clone directly, and programs calling unshare, causing the glibc pthread_atfork hook to not get called. It would be better to have the kernel take care of this automatically. The patch also adds MADV_KEEPONFORK, to undo the effects of a prior MADV_WIPEONFORK. This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO: https://man.openbsd.org/minherit.2 [akpm@linux-foundation.org: numerically order arch/parisc/include/uapi/asm/mman.h #defines] Link: http://lkml.kernel.org/r/20170811212829.29186-3-riel@redhat.com Signed-off-by: Rik van Riel Reported-by: Florian Weimer Reported-by: Colm MacCártaigh Reviewed-by: Mike Kravetz Cc: "H. Peter Anvin" Cc: "Kirill A. Shutemov" Cc: Andy Lutomirski Cc: Dave Hansen Cc: Ingo Molnar Cc: Helge Deller Cc: Kees Cook Cc: Matthew Wilcox Cc: Thomas Gleixner Cc: Will Drewry Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/include/uapi/asm/mman.h | 3 +++ arch/mips/include/uapi/asm/mman.h | 3 +++ arch/parisc/include/uapi/asm/mman.h | 3 +++ arch/xtensa/include/uapi/asm/mman.h | 3 +++ 4 files changed, 12 insertions(+) (limited to 'arch') diff --git a/arch/alpha/include/uapi/asm/mman.h b/arch/alpha/include/uapi/asm/mman.h index 13b52aad3c43..3b26cc62dadb 100644 --- a/arch/alpha/include/uapi/asm/mman.h +++ b/arch/alpha/include/uapi/asm/mman.h @@ -64,6 +64,9 @@ overrides the coredump filter bits */ #define MADV_DODUMP 17 /* Clear the MADV_NODUMP flag */ +#define MADV_WIPEONFORK 18 /* Zero memory on fork, child only */ +#define MADV_KEEPONFORK 19 /* Undo MADV_WIPEONFORK */ + /* compatibility flags */ #define MAP_FILE 0 diff --git a/arch/mips/include/uapi/asm/mman.h b/arch/mips/include/uapi/asm/mman.h index 398eebcc3541..da3216007fe0 100644 --- a/arch/mips/include/uapi/asm/mman.h +++ b/arch/mips/include/uapi/asm/mman.h @@ -91,6 +91,9 @@ overrides the coredump filter bits */ #define MADV_DODUMP 17 /* Clear the MADV_NODUMP flag */ +#define MADV_WIPEONFORK 18 /* Zero memory on fork, child only */ +#define MADV_KEEPONFORK 19 /* Undo MADV_WIPEONFORK */ + /* compatibility flags */ #define MAP_FILE 0 diff --git a/arch/parisc/include/uapi/asm/mman.h b/arch/parisc/include/uapi/asm/mman.h index b87fbe3f338a..775b5d5e41a1 100644 --- a/arch/parisc/include/uapi/asm/mman.h +++ b/arch/parisc/include/uapi/asm/mman.h @@ -57,6 +57,9 @@ overrides the coredump filter bits */ #define MADV_DODUMP 70 /* Clear the MADV_NODUMP flag */ +#define MADV_WIPEONFORK 71 /* Zero memory on fork, child only */ +#define MADV_KEEPONFORK 72 /* Undo MADV_WIPEONFORK */ + #define MADV_HWPOISON 100 /* poison a page for testing */ #define MADV_SOFT_OFFLINE 101 /* soft offline page for testing */ diff --git a/arch/xtensa/include/uapi/asm/mman.h b/arch/xtensa/include/uapi/asm/mman.h index 8ce77a2e9bab..b15b278aa314 100644 --- a/arch/xtensa/include/uapi/asm/mman.h +++ b/arch/xtensa/include/uapi/asm/mman.h @@ -103,6 +103,9 @@ overrides the coredump filter bits */ #define MADV_DODUMP 17 /* Clear the MADV_NODUMP flag */ +#define MADV_WIPEONFORK 18 /* Zero memory on fork, child only */ +#define MADV_KEEPONFORK 19 /* Undo MADV_WIPEONFORK */ + /* compatibility flags */ #define MAP_FILE 0 -- cgit v1.2.3