[PATCHv2 17/29] x86/asm: remove __VIRTUAL_MASK_SHIFT==47 assert
From: Kirill A. Shutemov <hidden>
Date: 2016-12-27 01:55:59
Also in:
linux-arch, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit), x86 entry code · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski
We don't need it anymore. 17be0aec74fb ("x86/asm/entry/64: Implement
better check for canonical addresses") made canonical address check
generic wrt. address width.
Signed-off-by: Kirill A. Shutemov <redacted>
---
arch/x86/entry/entry_64.S | 7 ++-----
1 file changed, 2 insertions(+), 5 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 5b219707c2f2..a6b84c309685 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S@@ -264,12 +264,9 @@ return_from_SYSCALL_64: * * If width of "canonical tail" ever becomes variable, this will need * to be updated to remain correct on both old and new CPUs. + * + * Change top 16 bits to be the sign-extension of 47th bit */ - .ifne __VIRTUAL_MASK_SHIFT - 47 - .error "virtual address width changed -- SYSRET checks need update" - .endif - - /* Change top 16 bits to be the sign-extension of 47th bit */ shl $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx sar $(64 - (__VIRTUAL_MASK_SHIFT+1)), %rcx
--
2.11.0
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>