BMC/Intel-BMC/linux.git/arch/x86/kernel/irq_64.c, branch dev

x86/irq: Merge irq_regs & irq_stat

2015-05-10T10:34:27+00:00

Move irq_regs and irq_stat definitions to irq.c. Signed-off-by: Brian Gerst Cc: Andrew Morton Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1431185813-15413-2-git-send-email-brgerst@gmail.com Signed-off-by: Ingo Molnar

x86/asm/entry: Change all 'user_mode_vm()' calls to 'user_mode()'

2015-03-23T10:14:17+00:00

user_mode_vm() and user_mode() are now the same. Change all callers of user_mode_vm() to user_mode(). The next patch will remove the definition of user_mode_vm. Signed-off-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brad Spengler Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/43b1f57f3df70df5a08b0925897c660725015554.1426728647.git.luto@kernel.org [ Merged to a more recent kernel. ] Signed-off-by: Ingo Molnar

x86: Replace __get_cpu_var uses

2014-08-26T17:45:49+00:00

__get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: Thomas Gleixner Cc: x86@kernel.org Acked-by: H. Peter Anvin Acked-by: Ingo Molnar Signed-off-by: Christoph Lameter Signed-off-by: Tejun Heo

irq: Consolidate do_softirq() arch overriden implementations

2013-10-01T10:53:25+00:00

All arch overriden implementations of do_softirq() share the following common code: disable irqs (to avoid races with the pending check), check if there are softirqs pending, then execute __do_softirq() on a specific stack. Consolidate the common parts such that archs only worry about the stack switch. Acked-by: Linus Torvalds Signed-off-by: Frederic Weisbecker Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Paul Mackerras Cc: James Hogan Cc: James E.J. Bottomley Cc: Helge Deller Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: David S. Miller Cc: Andrew Morton

x86: Add stack top margin for stack overflow checking

2011-12-07T08:27:11+00:00

It seems that a margin for stack overflow checking is added to top of a kernel stack but is not added to IRQ and exception stacks in stack_overflow_check(). Therefore, the overflows of IRQ and exception stacks are always detected only after they actually occurred and data corruption might occur due to them. This patch adds the margin to top of IRQ and exception stacks as well as a kernel stack to enhance reliability. Signed-off-by: Mitsuo Hayasaka Cc: yrl.pp-manager.tt@hitachi.com Cc: Linus Torvalds Cc: Andrew Morton Link: http://lkml.kernel.org/r/20111207082910.9847.3359.stgit@ltc219.sdl.hitachi.co.jp [ removed the #undef - we typically don't do that for uncommon names ] Signed-off-by: Ingo Molnar

x86: Clean up the range of stack overflow checking

2011-12-05T10:37:48+00:00

The overflow checking of kernel stack checks if the stack pointer points to the available kernel stack range, which is derived from the original overflow checking. It is clear that curbase address is always less than low boundary of available kernel stack. So, this patch removes the first condition that checks if the pointer is higher than curbase. Signed-off-by: Mitsuo Hayasaka Cc: yrl.pp-manager.tt@hitachi.com Cc: Randy Dunlap Link: http://lkml.kernel.org/r/20111129060845.11076.40916.stgit@ltc219.sdl.hitachi.co.jp Signed-off-by: Ingo Molnar Cc: "H. Peter Anvin"

x86: Panic on detection of stack overflow

2011-12-05T10:37:47+00:00

Currently, messages are just output on the detection of stack overflow, which is not sufficient for systems that need a high reliability. This is because in general the overflow may corrupt data, and the additional corruption may occur due to reading them unless systems stop. This patch adds the sysctl parameter kernel.panic_on_stackoverflow and causes a panic when detecting the overflows of kernel, IRQ and exception stacks except user stack according to the parameter. It is disabled by default. Signed-off-by: Mitsuo Hayasaka Cc: yrl.pp-manager.tt@hitachi.com Cc: Randy Dunlap Cc: "H. Peter Anvin" Link: http://lkml.kernel.org/r/20111129060836.11076.12323.stgit@ltc219.sdl.hitachi.co.jp Signed-off-by: Ingo Molnar

x86: Check stack overflow in detail

2011-12-05T10:37:45+00:00

Currently, only kernel stack is checked for the overflow, which is not sufficient for systems that need a high reliability. To enhance it, it is required to check the IRQ and exception stacks, as well. This patch checks all the stack types and will cause messages of stacks in detail when free stack space drops below a certain limit except user stack. Signed-off-by: Mitsuo Hayasaka Cc: yrl.pp-manager.tt@hitachi.com Cc: Randy Dunlap Link: http://lkml.kernel.org/r/20111129060829.11076.51733.stgit@ltc219.sdl.hitachi.co.jp Signed-off-by: Ingo Molnar Cc: "H. Peter Anvin"

x86: Add user_mode_vm check in stack_overflow_check

2011-12-05T10:28:25+00:00

The kernel stack overflow is checked in stack_overflow_check(), which may wrongly detect the overflow if the stack pointer in user space points to the kernel stack intentionally or accidentally. So, the actual overflow is never detected after this misdetection because WARN_ONCE() is used on the detection of it. This patch adds user-mode-vm checking before it to avoid this problem and bails out early if the user stack is used. Signed-off-by: Mitsuo Hayasaka Cc: yrl.pp-manager.tt@hitachi.com Cc: Randy Dunlap Link: http://lkml.kernel.org/r/20111129060821.11076.55315.stgit@ltc219.sdl.hitachi.co.jp Signed-off-by: Ingo Molnar Cc: "H. Peter Anvin"

x86: Unify fixup_irqs() for 32-bit and 64-bit kernels

2009-11-02T14:56:34+00:00

There is no reason to have different fixup_irqs() for 32-bit and 64-bit kernels. Unify by using the superior 64-bit version for both the kernels. Signed-off-by: Suresh Siddha Signed-off-by: Gary Hade Cc: Eric W. Biederman LKML-Reference: <20091026230001.562512739@sbs-t61.sc.intel.com> Signed-off-by: Ingo Molnar