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authorLinus Torvalds <torvalds@linux-foundation.org>2016-02-20 20:32:40 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-02-20 20:32:40 +0300
commit0389075ecfb6231818de9b0225d3a5a21a661171 (patch)
tree991154188efee4117974d9aa5bcd7497257c7656 /Documentation
parent06b74c658c595e4ef9fd5746f927a1cb6c3a59d5 (diff)
parentf4eafd8bcd5229e998aa252627703b8462c3b90f (diff)
downloadlinux-0389075ecfb6231818de9b0225d3a5a21a661171.tar.xz
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar: "This is unusually large, partly due to the EFI fixes that prevent accidental deletion of EFI variables through efivarfs that may brick machines. These fixes are somewhat involved to maintain compatibility with existing install methods and other usage modes, while trying to turn off the 'rm -rf' bricking vector. Other fixes are for large page ioremap()s and for non-temporal user-memcpy()s" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/mm: Fix vmalloc_fault() to handle large pages properly hpet: Drop stale URLs x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache() x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable lib/ucs2_string: Correct ucs2 -> utf8 conversion efi: Add pstore variables to the deletion whitelist efi: Make efivarfs entries immutable by default efi: Make our variable validation list include the guid efi: Do variable name validation tests in utf8 efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version lib/ucs2_string: Add ucs2 -> utf8 helper functions
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/filesystems/efivarfs.txt7
-rw-r--r--Documentation/timers/hpet.txt4
2 files changed, 8 insertions, 3 deletions
diff --git a/Documentation/filesystems/efivarfs.txt b/Documentation/filesystems/efivarfs.txt
index c477af086e65..686a64bba775 100644
--- a/Documentation/filesystems/efivarfs.txt
+++ b/Documentation/filesystems/efivarfs.txt
@@ -14,3 +14,10 @@ filesystem.
efivarfs is typically mounted like this,
mount -t efivarfs none /sys/firmware/efi/efivars
+
+Due to the presence of numerous firmware bugs where removing non-standard
+UEFI variables causes the system firmware to fail to POST, efivarfs
+files that are not well-known standardized variables are created
+as immutable files. This doesn't prevent removal - "chattr -i" will work -
+but it does prevent this kind of failure from being accomplished
+accidentally.
diff --git a/Documentation/timers/hpet.txt b/Documentation/timers/hpet.txt
index 767392ffd31e..a484d2c109d7 100644
--- a/Documentation/timers/hpet.txt
+++ b/Documentation/timers/hpet.txt
@@ -1,9 +1,7 @@
High Precision Event Timer Driver for Linux
The High Precision Event Timer (HPET) hardware follows a specification
-by Intel and Microsoft which can be found at
-
- http://www.intel.com/hardwaredesign/hpetspec_1.pdf
+by Intel and Microsoft, revision 1.
Each HPET has one fixed-rate counter (at 10+ MHz, hence "High Precision")
and up to 32 comparators. Normally three or more comparators are provided,