From 3fc2579e6f162fcff964f5aa01c8a29438ca5c05 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 3 Jan 2019 15:26:41 -0800 Subject: fls: change parameter to unsigned int When testing in userspace, UBSAN pointed out that shifting into the sign bit is undefined behaviour. It doesn't really make sense to ask for the highest set bit of a negative value, so just turn the argument type into an unsigned int. Some architectures (eg ppc) already had it declared as an unsigned int, so I don't expect too many problems. Link: http://lkml.kernel.org/r/20181105221117.31828-1-willy@infradead.org Signed-off-by: Matthew Wilcox Acked-by: Thomas Gleixner Acked-by: Geert Uytterhoeven Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/include/asm/bitops.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/alpha/include/asm') diff --git a/arch/alpha/include/asm/bitops.h b/arch/alpha/include/asm/bitops.h index ca43f4d0b937..5adca78830b5 100644 --- a/arch/alpha/include/asm/bitops.h +++ b/arch/alpha/include/asm/bitops.h @@ -391,9 +391,9 @@ static inline unsigned long __fls(unsigned long x) return fls64(x) - 1; } -static inline int fls(int x) +static inline int fls(unsigned int x) { - return fls64((unsigned int) x); + return fls64(x); } /* -- cgit v1.2.3 From 4cf58924951ef80eec636b863e7a53973c44261a Mon Sep 17 00:00:00 2001 From: "Joel Fernandes (Google)" Date: Thu, 3 Jan 2019 15:28:34 -0800 Subject: mm: treewide: remove unused address argument from pte_alloc functions Patch series "Add support for fast mremap". This series speeds up the mremap(2) syscall by copying page tables at the PMD level even for non-THP systems. There is concern that the extra 'address' argument that mremap passes to pte_alloc may do something subtle architecture related in the future that may make the scheme not work. Also we find that there is no point in passing the 'address' to pte_alloc since its unused. This patch therefore removes this argument tree-wide resulting in a nice negative diff as well. Also ensuring along the way that the enabled architectures do not do anything funky with the 'address' argument that goes unnoticed by the optimization. Build and boot tested on x86-64. Build tested on arm64. The config enablement patch for arm64 will be posted in the future after more testing. The changes were obtained by applying the following Coccinelle script. (thanks Julia for answering all Coccinelle questions!). Following fix ups were done manually: * Removal of address argument from pte_fragment_alloc * Removal of pte_alloc_one_fast definitions from m68k and microblaze. // Options: --include-headers --no-includes // Note: I split the 'identifier fn' line, so if you are manually // running it, please unsplit it so it runs for you. virtual patch @pte_alloc_func_def depends on patch exists@ identifier E2; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; type T2; @@ fn(... - , T2 E2 ) { ... } @pte_alloc_func_proto_noarg depends on patch exists@ type T1, T2, T3, T4; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ ( - T3 fn(T1, T2); + T3 fn(T1); | - T3 fn(T1, T2, T4); + T3 fn(T1, T2); ) @pte_alloc_func_proto depends on patch exists@ identifier E1, E2, E4; type T1, T2, T3, T4; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ ( - T3 fn(T1 E1, T2 E2); + T3 fn(T1 E1); | - T3 fn(T1 E1, T2 E2, T4 E4); + T3 fn(T1 E1, T2 E2); ) @pte_alloc_func_call depends on patch exists@ expression E2; identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; @@ fn(... -, E2 ) @pte_alloc_macro depends on patch exists@ identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$"; identifier a, b, c; expression e; position p; @@ ( - #define fn(a, b, c) e + #define fn(a, b) e | - #define fn(a, b) e + #define fn(a) e ) Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com Signed-off-by: Joel Fernandes (Google) Suggested-by: Kirill A. Shutemov Acked-by: Kirill A. Shutemov Cc: Michal Hocko Cc: Julia Lawall Cc: Kirill A. Shutemov Cc: William Kucharski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/alpha/include/asm/pgalloc.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/alpha/include/asm') diff --git a/arch/alpha/include/asm/pgalloc.h b/arch/alpha/include/asm/pgalloc.h index ab3e3a8638fb..02f9f91bb4f0 100644 --- a/arch/alpha/include/asm/pgalloc.h +++ b/arch/alpha/include/asm/pgalloc.h @@ -52,7 +52,7 @@ pmd_free(struct mm_struct *mm, pmd_t *pmd) } static inline pte_t * -pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) +pte_alloc_one_kernel(struct mm_struct *mm) { pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO); return pte; @@ -65,9 +65,9 @@ pte_free_kernel(struct mm_struct *mm, pte_t *pte) } static inline pgtable_t -pte_alloc_one(struct mm_struct *mm, unsigned long address) +pte_alloc_one(struct mm_struct *mm) { - pte_t *pte = pte_alloc_one_kernel(mm, address); + pte_t *pte = pte_alloc_one_kernel(mm); struct page *page; if (!pte) -- cgit v1.2.3