Commit 0ccb32c9 authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

s390/mm: align swapper_pg_dir to 16k 



The segment/region table that is part of the kernel image must be
properly aligned to 16k in order to make the crdte inline assembly
work.
Otherwise it will calculate a wrong segment/region table start address
and access incorrect memory locations if the swapper_pg_dir is not
aligned to 16k.

Therefore define BSS_FIRST_SECTIONS in order to put the swapper_pg_dir
at the beginning of the bss section and also align the bss section to
16k just like other architectures did.

Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 4b8fe77a

arch/s390/include/asm/pgtable.h

+1 −1
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ 
#include <asm/bug.h>

#include <asm/page.h>



extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));

extern pgd_t swapper_pg_dir[];

extern void paging_init(void);

extern void vmem_map_init(void);

pmd_t *vmem_pmd_alloc(void);

arch/s390/kernel/vmlinux.lds.S

+8 −1
Original line number Diff line number Diff line
@@ -4,6 +4,13 @@ 


#include <asm/thread_info.h>

#include <asm/page.h>



/*

 * Put .bss..swapper_pg_dir as the first thing in .bss. This will

 * make sure it has 16k alignment.

 */

#define BSS_FIRST_SECTIONS *(.bss..swapper_pg_dir)



#include <asm-generic/vmlinux.lds.h>



OUTPUT_FORMAT("elf64-s390", "elf64-s390", "elf64-s390")
@@ -81,7 +88,7 @@ SECTIONS 
	. = ALIGN(PAGE_SIZE);

	__init_end = .;		/* freed after init ends here */



	BSS_SECTION(0, 2, 0)

	BSS_SECTION(PAGE_SIZE, 4 * PAGE_SIZE, PAGE_SIZE)



	_end = . ;

arch/s390/mm/init.c

+1 −1
Original line number Diff line number Diff line
@@ -40,7 +40,7 @@ 
#include <asm/ctl_reg.h>

#include <asm/sclp.h>



pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));

pgd_t swapper_pg_dir[PTRS_PER_PGD] __section(.bss..swapper_pg_dir);



unsigned long empty_zero_page, zero_page_mask;

EXPORT_SYMBOL(empty_zero_page);

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