x86, vdso: Patch alternatives in the 32-bit VDSO
We need the alternatives mechanism for rdtsc_barrier() to work. Signed-off-by: Stefani Seibold <stefani@seibold.net> Link: http://lkml.kernel.org/r/1395094933-14252-9-git-send-email-stefani@seibold.net Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Andy Lutomirski
H. Peter Anvin
parent
ef721987ae
commit
b4b541a610
4 changed files with 26 additions and 15 deletions
|
|
@ -28,4 +28,6 @@ extern const char vdso32_int80_start, vdso32_int80_end;
|
||||||
extern const char vdso32_syscall_start, vdso32_syscall_end;
|
extern const char vdso32_syscall_start, vdso32_syscall_end;
|
||||||
extern const char vdso32_sysenter_start, vdso32_sysenter_end;
|
extern const char vdso32_sysenter_start, vdso32_sysenter_end;
|
||||||
|
|
||||||
|
void __init patch_vdso32(void *vdso, size_t len);
|
||||||
|
|
||||||
#endif /* _ASM_X86_VDSO_H */
|
#endif /* _ASM_X86_VDSO_H */
|
||||||
|
|
|
||||||
|
|
@ -21,7 +21,8 @@ vobjs-$(VDSOX32-y) += $(vobjx32s-compat)
|
||||||
vobj64s := $(filter-out $(vobjx32s-compat),$(vobjs-y))
|
vobj64s := $(filter-out $(vobjx32s-compat),$(vobjs-y))
|
||||||
|
|
||||||
# files to link into kernel
|
# files to link into kernel
|
||||||
obj-$(VDSO64-y) += vma.o vdso.o
|
obj-y += vma.o
|
||||||
|
obj-$(VDSO64-y) += vdso.o
|
||||||
obj-$(VDSOX32-y) += vdsox32.o
|
obj-$(VDSOX32-y) += vdsox32.o
|
||||||
obj-$(VDSO32-y) += vdso32.o vdso32-setup.o
|
obj-$(VDSO32-y) += vdso32.o vdso32-setup.o
|
||||||
|
|
||||||
|
|
|
||||||
|
|
@ -112,24 +112,25 @@ void enable_sep_cpu(void)
|
||||||
|
|
||||||
int __init sysenter_setup(void)
|
int __init sysenter_setup(void)
|
||||||
{
|
{
|
||||||
void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
|
void *vdso_page = (void *)get_zeroed_page(GFP_ATOMIC);
|
||||||
const void *vsyscall;
|
const void *vdso;
|
||||||
size_t vsyscall_len;
|
size_t vdso_len;
|
||||||
|
|
||||||
vdso32_pages[0] = virt_to_page(syscall_page);
|
vdso32_pages[0] = virt_to_page(vdso_page);
|
||||||
|
|
||||||
if (vdso32_syscall()) {
|
if (vdso32_syscall()) {
|
||||||
vsyscall = &vdso32_syscall_start;
|
vdso = &vdso32_syscall_start;
|
||||||
vsyscall_len = &vdso32_syscall_end - &vdso32_syscall_start;
|
vdso_len = &vdso32_syscall_end - &vdso32_syscall_start;
|
||||||
} else if (vdso32_sysenter()){
|
} else if (vdso32_sysenter()){
|
||||||
vsyscall = &vdso32_sysenter_start;
|
vdso = &vdso32_sysenter_start;
|
||||||
vsyscall_len = &vdso32_sysenter_end - &vdso32_sysenter_start;
|
vdso_len = &vdso32_sysenter_end - &vdso32_sysenter_start;
|
||||||
} else {
|
} else {
|
||||||
vsyscall = &vdso32_int80_start;
|
vdso = &vdso32_int80_start;
|
||||||
vsyscall_len = &vdso32_int80_end - &vdso32_int80_start;
|
vdso_len = &vdso32_int80_end - &vdso32_int80_start;
|
||||||
}
|
}
|
||||||
|
|
||||||
memcpy(syscall_page, vsyscall, vsyscall_len);
|
memcpy(vdso_page, vdso, vdso_len);
|
||||||
|
patch_vdso32(vdso_page, vdso_len);
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
|
|
|
||||||
|
|
@ -16,6 +16,7 @@
|
||||||
#include <asm/vdso.h>
|
#include <asm/vdso.h>
|
||||||
#include <asm/page.h>
|
#include <asm/page.h>
|
||||||
|
|
||||||
|
#if defined(CONFIG_X86_64)
|
||||||
unsigned int __read_mostly vdso_enabled = 1;
|
unsigned int __read_mostly vdso_enabled = 1;
|
||||||
|
|
||||||
extern char vdso_start[], vdso_end[];
|
extern char vdso_start[], vdso_end[];
|
||||||
|
|
@ -28,8 +29,12 @@ static unsigned vdso_size;
|
||||||
extern char vdsox32_start[], vdsox32_end[];
|
extern char vdsox32_start[], vdsox32_end[];
|
||||||
extern struct page *vdsox32_pages[];
|
extern struct page *vdsox32_pages[];
|
||||||
static unsigned vdsox32_size;
|
static unsigned vdsox32_size;
|
||||||
|
#endif
|
||||||
|
#endif
|
||||||
|
|
||||||
static void __init patch_vdsox32(void *vdso, size_t len)
|
#if defined(CONFIG_X86_32) || defined(CONFIG_X86_X32_ABI) || \
|
||||||
|
defined(CONFIG_COMPAT)
|
||||||
|
void __init patch_vdso32(void *vdso, size_t len)
|
||||||
{
|
{
|
||||||
Elf32_Ehdr *hdr = vdso;
|
Elf32_Ehdr *hdr = vdso;
|
||||||
Elf32_Shdr *sechdrs, *alt_sec = 0;
|
Elf32_Shdr *sechdrs, *alt_sec = 0;
|
||||||
|
|
@ -52,7 +57,7 @@ static void __init patch_vdsox32(void *vdso, size_t len)
|
||||||
}
|
}
|
||||||
|
|
||||||
/* If we get here, it's probably a bug. */
|
/* If we get here, it's probably a bug. */
|
||||||
pr_warning("patch_vdsox32: .altinstructions not found\n");
|
pr_warning("patch_vdso32: .altinstructions not found\n");
|
||||||
return; /* nothing to patch */
|
return; /* nothing to patch */
|
||||||
|
|
||||||
found:
|
found:
|
||||||
|
|
@ -61,6 +66,7 @@ found:
|
||||||
}
|
}
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
|
#if defined(CONFIG_X86_64)
|
||||||
static void __init patch_vdso64(void *vdso, size_t len)
|
static void __init patch_vdso64(void *vdso, size_t len)
|
||||||
{
|
{
|
||||||
Elf64_Ehdr *hdr = vdso;
|
Elf64_Ehdr *hdr = vdso;
|
||||||
|
|
@ -104,7 +110,7 @@ static int __init init_vdso(void)
|
||||||
vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE);
|
vdso_pages[i] = virt_to_page(vdso_start + i*PAGE_SIZE);
|
||||||
|
|
||||||
#ifdef CONFIG_X86_X32_ABI
|
#ifdef CONFIG_X86_X32_ABI
|
||||||
patch_vdsox32(vdsox32_start, vdsox32_end - vdsox32_start);
|
patch_vdso32(vdsox32_start, vdsox32_end - vdsox32_start);
|
||||||
npages = (vdsox32_end - vdsox32_start + PAGE_SIZE - 1) / PAGE_SIZE;
|
npages = (vdsox32_end - vdsox32_start + PAGE_SIZE - 1) / PAGE_SIZE;
|
||||||
vdsox32_size = npages << PAGE_SHIFT;
|
vdsox32_size = npages << PAGE_SHIFT;
|
||||||
for (i = 0; i < npages; i++)
|
for (i = 0; i < npages; i++)
|
||||||
|
|
@ -204,3 +210,4 @@ static __init int vdso_setup(char *s)
|
||||||
return 0;
|
return 0;
|
||||||
}
|
}
|
||||||
__setup("vdso=", vdso_setup);
|
__setup("vdso=", vdso_setup);
|
||||||
|
#endif
|
||||||
|
|
|
||||||
Loading…
Add table
Reference in a new issue