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authorLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 13:07:55 -0700
committerLinus Torvalds <torvalds@g5.osdl.org>2006-09-26 13:07:55 -0700
commitb278240839e20fa9384ea430df463b367b90e04e (patch)
treef99f0c8cdd4cc7f177cd75440e6bd181cded7fb3 /Documentation
parentdd77a4ee0f3981693d4229aa1d57cea9e526ff47 (diff)
parent3f75f42d7733e73aca5c78326489efd4189e0111 (diff)
Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (225 commits) [PATCH] Don't set calgary iommu as default y [PATCH] i386/x86-64: New Intel feature flags [PATCH] x86: Add a cumulative thermal throttle event counter. [PATCH] i386: Make the jiffies compares use the 64bit safe macros. [PATCH] x86: Refactor thermal throttle processing [PATCH] Add 64bit jiffies compares (for use with get_jiffies_64) [PATCH] Fix unwinder warning in traps.c [PATCH] x86: Allow disabling early pci scans with pci=noearly or disallowing conf1 [PATCH] x86: Move direct PCI scanning functions out of line [PATCH] i386/x86-64: Make all early PCI scans dependent on CONFIG_PCI [PATCH] Don't leak NT bit into next task [PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder [PATCH] Fix some broken white space in ia32_signal.c [PATCH] Initialize argument registers for 32bit signal handlers. [PATCH] Remove all traces of signal number conversion [PATCH] Don't synchronize time reading on single core AMD systems [PATCH] Remove outdated comment in x86-64 mmconfig code [PATCH] Use string instructions for Core2 copy/clear [PATCH] x86: - restore i8259A eoi status on resume [PATCH] i386: Split multi-line printk in oops output. ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/HOWTO3
-rw-r--r--Documentation/filesystems/proc.txt14
-rw-r--r--Documentation/kbuild/makefiles.txt5
-rw-r--r--Documentation/kernel-parameters.txt6
-rw-r--r--Documentation/x86_64/boot-options.txt7
-rw-r--r--Documentation/x86_64/kernel-stacks99
6 files changed, 127 insertions, 7 deletions
diff --git a/Documentation/HOWTO b/Documentation/HOWTO
index 915ae8c986c..1d6560413cc 100644
--- a/Documentation/HOWTO
+++ b/Documentation/HOWTO
@@ -358,7 +358,8 @@ Here is a list of some of the different kernel trees available:
quilt trees:
- USB, PCI, Driver Core, and I2C, Greg Kroah-Hartman <gregkh@suse.de>
kernel.org/pub/linux/kernel/people/gregkh/gregkh-2.6/
-
+ - x86-64, partly i386, Andi Kleen <ak@suse.de>
+ ftp.firstfloor.org:/pub/ak/x86_64/quilt/
Bug Reporting
-------------
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 99902ae6804..7db71d6fba8 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -1124,11 +1124,15 @@ debugging information is displayed on console.
NMI switch that most IA32 servers have fires unknown NMI up, for example.
If a system hangs up, try pressing the NMI switch.
-[NOTE]
- This function and oprofile share a NMI callback. Therefore this function
- cannot be enabled when oprofile is activated.
- And NMI watchdog will be disabled when the value in this file is set to
- non-zero.
+nmi_watchdog
+------------
+
+Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero
+the NMI watchdog is enabled and will continuously test all online cpus to
+determine whether or not they are still functioning properly.
+
+Because the NMI watchdog shares registers with oprofile, by disabling the NMI
+watchdog, oprofile may have more registers to utilize.
2.4 /proc/sys/vm - The virtual memory subsystem
diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index b7d6abb501a..e2cbd59cf2d 100644
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -421,6 +421,11 @@ more details, with real examples.
The second argument is optional, and if supplied will be used
if first argument is not supported.
+ as-instr
+ as-instr checks if the assembler reports a specific instruction
+ and then outputs either option1 or option2
+ C escapes are supported in the test instruction
+
cc-option
cc-option is used to check if $(CC) supports a given option, and not
supported to use an optional second option.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 766abdab94e..c918cc3f65f 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1240,7 +1240,11 @@ running once the system is up.
bootloader. This is currently used on
IXP2000 systems where the bus has to be
configured a certain way for adjunct CPUs.
-
+ noearly [X86] Don't do any early type 1 scanning.
+ This might help on some broken boards which
+ machine check when some devices' config space
+ is read. But various workarounds are disabled
+ and some IOMMU drivers will not work.
pcmv= [HW,PCMCIA] BadgePAD 4
pd. [PARIDE]
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index 6da24e7a56c..4303e0c1247 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -245,6 +245,13 @@ Debugging
newfallback: use new unwinder but fall back to old if it gets
stuck (default)
+ call_trace=[old|both|newfallback|new]
+ old: use old inexact backtracer
+ new: use new exact dwarf2 unwinder
+ both: print entries from both
+ newfallback: use new unwinder but fall back to old if it gets
+ stuck (default)
+
Misc
noreplacement Don't replace instructions with more appropriate ones
diff --git a/Documentation/x86_64/kernel-stacks b/Documentation/x86_64/kernel-stacks
new file mode 100644
index 00000000000..bddfddd466a
--- /dev/null
+++ b/Documentation/x86_64/kernel-stacks
@@ -0,0 +1,99 @@
+Most of the text from Keith Owens, hacked by AK
+
+x86_64 page size (PAGE_SIZE) is 4K.
+
+Like all other architectures, x86_64 has a kernel stack for every
+active thread. These thread stacks are THREAD_SIZE (2*PAGE_SIZE) big.
+These stacks contain useful data as long as a thread is alive or a
+zombie. While the thread is in user space the kernel stack is empty
+except for the thread_info structure at the bottom.
+
+In addition to the per thread stacks, there are specialized stacks
+associated with each cpu. These stacks are only used while the kernel
+is in control on that cpu, when a cpu returns to user space the
+specialized stacks contain no useful data. The main cpu stacks is
+
+* Interrupt stack. IRQSTACKSIZE
+
+ Used for external hardware interrupts. If this is the first external
+ hardware interrupt (i.e. not a nested hardware interrupt) then the
+ kernel switches from the current task to the interrupt stack. Like
+ the split thread and interrupt stacks on i386 (with CONFIG_4KSTACKS),
+ this gives more room for kernel interrupt processing without having
+ to increase the size of every per thread stack.
+
+ The interrupt stack is also used when processing a softirq.
+
+Switching to the kernel interrupt stack is done by software based on a
+per CPU interrupt nest counter. This is needed because x86-64 "IST"
+hardware stacks cannot nest without races.
+
+x86_64 also has a feature which is not available on i386, the ability
+to automatically switch to a new stack for designated events such as
+double fault or NMI, which makes it easier to handle these unusual
+events on x86_64. This feature is called the Interrupt Stack Table
+(IST). There can be up to 7 IST entries per cpu. The IST code is an
+index into the Task State Segment (TSS), the IST entries in the TSS
+point to dedicated stacks, each stack can be a different size.
+
+An IST is selected by an non-zero value in the IST field of an
+interrupt-gate descriptor. When an interrupt occurs and the hardware
+loads such a descriptor, the hardware automatically sets the new stack
+pointer based on the IST value, then invokes the interrupt handler. If
+software wants to allow nested IST interrupts then the handler must
+adjust the IST values on entry to and exit from the interrupt handler.
+(this is occasionally done, e.g. for debug exceptions)
+
+Events with different IST codes (i.e. with different stacks) can be
+nested. For example, a debug interrupt can safely be interrupted by an
+NMI. arch/x86_64/kernel/entry.S::paranoidentry adjusts the stack
+pointers on entry to and exit from all IST events, in theory allowing
+IST events with the same code to be nested. However in most cases, the
+stack size allocated to an IST assumes no nesting for the same code.
+If that assumption is ever broken then the stacks will become corrupt.
+
+The currently assigned IST stacks are :-
+
+* STACKFAULT_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
+
+ Used for interrupt 12 - Stack Fault Exception (#SS).
+
+ This allows to recover from invalid stack segments. Rarely
+ happens.
+
+* DOUBLEFAULT_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
+
+ Used for interrupt 8 - Double Fault Exception (#DF).
+
+ Invoked when handling a exception causes another exception. Happens
+ when the kernel is very confused (e.g. kernel stack pointer corrupt)
+ Using a separate stack allows to recover from it well enough in many
+ cases to still output an oops.
+
+* NMI_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
+
+ Used for non-maskable interrupts (NMI).
+
+ NMI can be delivered at any time, including when the kernel is in the
+ middle of switching stacks. Using IST for NMI events avoids making
+ assumptions about the previous state of the kernel stack.
+
+* DEBUG_STACK. DEBUG_STKSZ
+
+ Used for hardware debug interrupts (interrupt 1) and for software
+ debug interrupts (INT3).
+
+ When debugging a kernel, debug interrupts (both hardware and
+ software) can occur at any time. Using IST for these interrupts
+ avoids making assumptions about the previous state of the kernel
+ stack.
+
+* MCE_STACK. EXCEPTION_STKSZ (PAGE_SIZE).
+
+ Used for interrupt 18 - Machine Check Exception (#MC).
+
+ MCE can be delivered at any time, including when the kernel is in the
+ middle of switching stacks. Using IST for MCE events avoids making
+ assumptions about the previous state of the kernel stack.
+
+For more details see the Intel IA32 or AMD AMD64 architecture manuals.