sparc: Fix -Wstringop-overflow warning (deba804c) · Commits · 戴 / test

Greetings, GCC 7 introduced the -Wstringop-overflow flag to detect buffer overflows in calls to string handling functions [1][2]. Due to the way ``empty_zero_page'' is declared in arch/sparc/include/setup.h, this causes a warning to trigger at compile time in the function mem_init(), which is subsequently converted to an error. The ensuing patch fixes this issue and aligns the declaration of empty_zero_page to that of other architectures. Thank you. Cheers, Orlando. [1] https://gcc.gnu.org/ml/gcc-patches/2016-10/msg02308.html [2] https://gcc.gnu.org/gcc-7/changes.html Signed-off-by:

Orlando Arias <oarias@knights.ucf.edu> -------------------------------------------------------------------------------- Signed-off-by:

David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/pgtable_32.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -91,9 +91,9 @@ extern unsigned long pfn_base;
		* ZERO_PAGE is a global shared page that is always zero: used
		* for zero-mapped memory areas etc..
		*/
		extern unsigned long empty_zero_page;
		extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];

		#define ZERO_PAGE(vaddr) (virt_to_page(&empty_zero_page))
		#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

		/*
		* In general all page table modifications should use the V8 atomic

arch/sparc/include/asm/setup.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -16,7 +16,7 @@ extern char reboot_command[];
		*/
		extern unsigned char boot_cpu_id;

		extern unsigned long empty_zero_page;
		extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];

		extern int serial_console;
		static inline int con_is_present(void)

arch/sparc/mm/init_32.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -290,7 +290,7 @@ void __init mem_init(void)


		/* Saves us work later. */
		memset((void *)&empty_zero_page, 0, PAGE_SIZE);
		memset((void *)empty_zero_page, 0, PAGE_SIZE);

		i = last_valid_pfn >> ((20 - PAGE_SHIFT) + 5);
		i += 1;

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