[tip: x86/cleanups] x86/asm: Fixup TASK_SIZE_MAX comment

From: tip-bot2 for Alexey Dobriyan
Date: Fri Feb 05 2021 - 04:46:26 EST


The following commit has been merged into the x86/cleanups branch of tip:

Commit-ID: 4f63b320afdd9af406f4426b0ff1a2cdb23e5b8d
Gitweb: https://git.kernel.org/tip/4f63b320afdd9af406f4426b0ff1a2cdb23e5b8d
Author: Alexey Dobriyan <adobriyan@xxxxxxxxx>
AuthorDate: Thu, 05 Mar 2020 21:17:19 +03:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Fri, 05 Feb 2021 10:37:39 +01:00

x86/asm: Fixup TASK_SIZE_MAX comment

Comment says "by preventing anything executable" which is not true. Even
PROT_NONE mapping can't be installed at (1<<47 - 4096).

mmap(0x7ffffffff000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = -1 ENOMEM

[ bp: Fixup to the moved location in page_64_types.h. ]

Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Reviewed-by: Andy Lutomirski <luto@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/20200305181719.GA5490@avx2
---
arch/x86/include/asm/page_64_types.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index 645bd1d..64297ea 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -66,7 +66,7 @@
* On Intel CPUs, if a SYSCALL instruction is at the highest canonical
* address, then that syscall will enter the kernel with a
* non-canonical return address, and SYSRET will explode dangerously.
- * We avoid this particular problem by preventing anything executable
+ * We avoid this particular problem by preventing anything
* from being mapped at the maximum canonical address.
*
* On AMD CPUs in the Ryzen family, there's a nasty bug in which the