Commit 269af9a1 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull exception table generation updates from Ingo Molnar:
 "The biggest change here is to allow the build-time sorting of the
  exception table, to speed up booting.  This is achieved by the
  architecture enabling BUILDTIME_EXTABLE_SORT.  This option is enabled
  for x86 and MIPS currently.

  On x86 a number of fixes and changes were needed to allow build-time
  sorting of the exception table, in particular a relocation invariant
  exception table format was needed.  This required the abstracting out
  of exception table protocol and the removal of 20 years of accumulated
  assumptions about the x86 exception table format.

  While at it, this tree also cleans up various other aspects of
  exception handling, such as early(er) exception handling for
  rdmsr_safe() et al.

  All in one, as the result of these changes the x86 exception code is
  now pretty nice and modern.  As an added bonus any regressions in this
  code will be early and violent crashes, so if you see any of those,
  you'll know whom to blame!"

Fix up trivial conflicts in arch/{mips,x86}/Kconfig files due to nearby
modifications of other core architecture options.

* 'x86-extable-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits)
  Revert "x86, extable: Disable presorted exception table for now"
  scripts/sortextable: Handle relative entries, and other cleanups
  x86, extable: Switch to relative exception table entries
  x86, extable: Disable presorted exception table for now
  x86, extable: Add _ASM_EXTABLE_EX() macro
  x86, extable: Remove open-coded exception table entries in arch/x86/ia32/ia32entry.S
  x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/xsave.h
  x86, extable: Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h
  x86, extable: Remove the now-unused __ASM_EX_SEC macros
  x86, extable: Remove open-coded exception table entries in arch/x86/xen/xen-asm_32.S
  x86, extable: Remove open-coded exception table entries in arch/x86/um/checksum_32.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/usercopy_32.c
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/putuser.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/getuser.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/csum-copy_64.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_nocache_64.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/copy_user_64.S
  x86, extable: Remove open-coded exception table entries in arch/x86/lib/checksum_32.S
  x86, extable: Remove open-coded exception table entries in arch/x86/kernel/test_rodata.c
  x86, extable: Remove open-coded exception table entries in arch/x86/kernel/entry_64.S
  ...
parents 8ca038dc 8b5ad472

Makefile

+10 −0
Original line number Diff line number Diff line
@@ -796,6 +796,10 @@ quiet_cmd_vmlinux_version = GEN .version 
quiet_cmd_sysmap = SYSMAP

      cmd_sysmap = $(CONFIG_SHELL) $(srctree)/scripts/mksysmap



# Sort exception table at build time

quiet_cmd_sortextable = SORTEX

      cmd_sortextable = $(objtree)/scripts/sortextable



# Link of vmlinux

# If CONFIG_KALLSYMS is set .version is already updated

# Generate System.map and verify that the content is consistent
@@ -808,6 +812,12 @@ define rule_vmlinux__ 
	$(call cmd,vmlinux__)

	$(Q)echo 'cmd_$@ := $(cmd_vmlinux__)' > $(@D)/.$(@F).cmd



	$(if $(CONFIG_BUILDTIME_EXTABLE_SORT),				\

	  $(Q)$(if $($(quiet)cmd_sortextable),				\

	    echo '  $($(quiet)cmd_sortextable)  vmlinux' &&)		\

	  $(cmd_sortextable)  vmlinux)





	$(Q)$(if $($(quiet)cmd_sysmap),                                      \

	  echo '  $($(quiet)cmd_sysmap)  System.map' &&)                     \

	$(cmd_sysmap) $@ System.map;                                         \

arch/mips/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ config MIPS 
	select HAVE_MEMBLOCK_NODE_MAP

	select ARCH_DISCARD_MEMBLOCK

	select GENERIC_SMP_IDLE_THREAD

	select BUILDTIME_EXTABLE_SORT



menu "Machine selection"

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -83,6 +83,7 @@ config X86 
	select DCACHE_WORD_ACCESS

	select GENERIC_SMP_IDLE_THREAD

	select HAVE_ARCH_SECCOMP_FILTER

	select BUILDTIME_EXTABLE_SORT



config INSTRUCTION_DECODER

	def_bool (KPROBES || PERF_EVENTS)

arch/x86/ia32/ia32entry.S

+3 −6
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
#include <asm/thread_info.h>	

#include <asm/segment.h>

#include <asm/irqflags.h>

#include <asm/asm.h>

#include <linux/linkage.h>

#include <linux/err.h>
@@ -146,9 +147,7 @@ ENTRY(ia32_sysenter_target) 
 	/* no need to do an access_ok check here because rbp has been

 	   32bit zero extended */ 

1:	movl	(%rbp),%ebp

 	.section __ex_table,"a"

 	.quad 1b,ia32_badarg

 	.previous	

	_ASM_EXTABLE(1b,ia32_badarg)

	orl     $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)

	testl   $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)

	CFI_REMEMBER_STATE
@@ -303,9 +302,7 @@ ENTRY(ia32_cstar_target) 
	   32bit zero extended */ 

	/* hardware stack frame is complete now */	

1:	movl	(%r8),%r9d

	.section __ex_table,"a"

	.quad 1b,ia32_badarg

	.previous	

	_ASM_EXTABLE(1b,ia32_badarg)

	orl     $TS_COMPAT,TI_status+THREAD_INFO(%rsp,RIP-ARGOFFSET)

	testl   $_TIF_WORK_SYSCALL_ENTRY,TI_flags+THREAD_INFO(%rsp,RIP-ARGOFFSET)

	CFI_REMEMBER_STATE

arch/x86/include/asm/asm.h

+26 −12
Original line number Diff line number Diff line
@@ -4,11 +4,9 @@ 
#ifdef __ASSEMBLY__

# define __ASM_FORM(x)	x

# define __ASM_FORM_COMMA(x) x,

# define __ASM_EX_SEC	.section __ex_table, "a"

#else

# define __ASM_FORM(x)	" " #x " "

# define __ASM_FORM_COMMA(x) " " #x ","

# define __ASM_EX_SEC	" .section __ex_table,\"a\"\n"

#endif



#ifdef CONFIG_X86_32
@@ -43,16 +41,32 @@ 
/* Exception table entry */

#ifdef __ASSEMBLY__

# define _ASM_EXTABLE(from,to)					\

	__ASM_EX_SEC ;		    \

	_ASM_ALIGN ;		    \

	_ASM_PTR from , to ;	    \

	.previous

	.pushsection "__ex_table","a" ;				\

	.balign 8 ;						\

	.long (from) - . ;					\

	.long (to) - . ;					\

	.popsection



# define _ASM_EXTABLE_EX(from,to)				\

	.pushsection "__ex_table","a" ;				\

	.balign 8 ;						\

	.long (from) - . ;					\

	.long (to) - . + 0x7ffffff0 ;				\

	.popsection

#else

# define _ASM_EXTABLE(from,to)					\

	__ASM_EX_SEC	\

	_ASM_ALIGN "\n" \

	_ASM_PTR #from "," #to "\n" \

	" .previous\n"

	" .pushsection \"__ex_table\",\"a\"\n"			\

	" .balign 8\n"						\

	" .long (" #from ") - .\n"				\

	" .long (" #to ") - .\n"				\

	" .popsection\n"



# define _ASM_EXTABLE_EX(from,to)				\

	" .pushsection \"__ex_table\",\"a\"\n"			\

	" .balign 8\n"						\

	" .long (" #from ") - .\n"				\

	" .long (" #to ") - . + 0x7ffffff0\n"			\

	" .popsection\n"

#endif



#endif /* _ASM_X86_ASM_H */

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