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authorAlexandre Ghiti2019-09-23 15:38:47 -0700
committerLinus Torvalds2019-09-24 15:54:11 -0700
commit67f3977f805b34cf0e41090679800d2091d41d49 (patch)
tree890420983b1d78727127650080058e6fea253d01 /arch/Kconfig
parente8d54b62c55ab6201de6d195fc2c276294c1f6ae (diff)
arm64, mm: move generic mmap layout functions to mm
arm64 handles top-down mmap layout in a way that can be easily reused by other architectures, so make it available in mm. It then introduces a new config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other architectures to benefit from those functions. Note that this new config depends on MMU being enabled, if selected without MMU support, a warning will be thrown. Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr Signed-off-by: Alexandre Ghiti <alex@ghiti.fr> Suggested-by: Christoph Hellwig <hch@infradead.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: James Hogan <jhogan@kernel.org> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/Kconfig')
-rw-r--r--arch/Kconfig10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/Kconfig b/arch/Kconfig
index 0fcf8ec1e098..dfce421b8e8a 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -706,6 +706,16 @@ config HAVE_ARCH_COMPAT_MMAP_BASES
and vice-versa 32-bit applications to call 64-bit mmap().
Required for applications doing different bitness syscalls.
+# This allows to use a set of generic functions to determine mmap base
+# address by giving priority to top-down scheme only if the process
+# is not in legacy mode (compat task, unlimited stack size or
+# sysctl_legacy_va_layout).
+# Architecture that selects this option can provide its own version of:
+# - STACK_RND_MASK
+config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
+ bool
+ depends on MMU
+
config HAVE_COPY_THREAD_TLS
bool
help