Commit-ID: 39d668e04edad25abe184fb329ce35a131146ee5 Gitweb: https://git.kernel.org/tip/39d668e04edad25abe184fb329ce35a131146ee5 Author: Joerg Roedel <[email protected]> AuthorDate: Wed, 18 Jul 2018 11:41:04 +0200 Committer: Thomas Gleixner <[email protected]> CommitDate: Fri, 20 Jul 2018 01:11:44 +0200
x86/mm/pti: Make pti_clone_kernel_text() compile on 32 bit The pti_clone_kernel_text() function references __end_rodata_hpage_align, which is only present on x86-64. This makes sense as the end of the rodata section is not huge-page aligned on 32 bit. Nevertheless a symbol is required for the function that points at the right address for both 32 and 64 bit. Introduce __end_rodata_aligned for that purpose and use it in pti_clone_kernel_text(). Signed-off-by: Joerg Roedel <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Pavel Machek <[email protected]> Cc: "H . Peter Anvin" <[email protected]> Cc: [email protected] Cc: Linus Torvalds <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Josh Poimboeuf <[email protected]> Cc: Juergen Gross <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Jiri Kosina <[email protected]> Cc: Boris Ostrovsky <[email protected]> Cc: Brian Gerst <[email protected]> Cc: David Laight <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: Eduardo Valentin <[email protected]> Cc: Greg KH <[email protected]> Cc: Will Deacon <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Andrea Arcangeli <[email protected]> Cc: Waiman Long <[email protected]> Cc: "David H . Gutteridge" <[email protected]> Cc: [email protected] Link: https://lkml.kernel.org/r/[email protected] --- arch/x86/include/asm/sections.h | 1 + arch/x86/kernel/vmlinux.lds.S | 17 ++++++++++------- arch/x86/mm/pti.c | 2 +- 3 files changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/x86/include/asm/sections.h b/arch/x86/include/asm/sections.h index 5c019d23d06b..4a911a382ade 100644 --- a/arch/x86/include/asm/sections.h +++ b/arch/x86/include/asm/sections.h @@ -7,6 +7,7 @@ extern char __brk_base[], __brk_limit[]; extern struct exception_table_entry __stop___ex_table[]; +extern char __end_rodata_aligned[]; #if defined(CONFIG_X86_64) extern char __end_rodata_hpage_align[]; diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 5e1458f609a1..8bde0a419f86 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -55,19 +55,22 @@ jiffies_64 = jiffies; * so we can enable protection checks as well as retain 2MB large page * mappings for kernel text. */ -#define X64_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE); +#define X86_ALIGN_RODATA_BEGIN . = ALIGN(HPAGE_SIZE); -#define X64_ALIGN_RODATA_END \ +#define X86_ALIGN_RODATA_END \ . = ALIGN(HPAGE_SIZE); \ - __end_rodata_hpage_align = .; + __end_rodata_hpage_align = .; \ + __end_rodata_aligned = .; #define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE); #define ALIGN_ENTRY_TEXT_END . = ALIGN(PMD_SIZE); #else -#define X64_ALIGN_RODATA_BEGIN -#define X64_ALIGN_RODATA_END +#define X86_ALIGN_RODATA_BEGIN +#define X86_ALIGN_RODATA_END \ + . = ALIGN(PAGE_SIZE); \ + __end_rodata_aligned = .; #define ALIGN_ENTRY_TEXT_BEGIN #define ALIGN_ENTRY_TEXT_END @@ -141,9 +144,9 @@ SECTIONS /* .text should occupy whole number of pages */ . = ALIGN(PAGE_SIZE); - X64_ALIGN_RODATA_BEGIN + X86_ALIGN_RODATA_BEGIN RO_DATA(PAGE_SIZE) - X64_ALIGN_RODATA_END + X86_ALIGN_RODATA_END /* Data */ .data : AT(ADDR(.data) - LOAD_OFFSET) { diff --git a/arch/x86/mm/pti.c b/arch/x86/mm/pti.c index a594e3b6401a..453d23760941 100644 --- a/arch/x86/mm/pti.c +++ b/arch/x86/mm/pti.c @@ -470,7 +470,7 @@ void pti_clone_kernel_text(void) * clone the areas past rodata, they might contain secrets. */ unsigned long start = PFN_ALIGN(_text); - unsigned long end = (unsigned long)__end_rodata_hpage_align; + unsigned long end = (unsigned long)__end_rodata_aligned; if (!pti_kernel_image_global_ok()) return;
