linux-toradex.git/arch/x86/kernel/tls.c, branch v3.2.15

x86, tls: Off by one limit check

2012-04-02T16:53:09+00:00

commit 8f0750f19789cf352d7e24a6cc50f2ab1b4f1372 upstream.

These are used as offsets into an array of GDT_ENTRY_TLS_ENTRIES members
so GDT_ENTRY_TLS_ENTRIES is one past the end of the array.

Signed-off-by: Dan Carpenter 
Link: http://lkml.kernel.org/r/20120324075250.GA28258@elgon.mountain
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

x86: Introducing asm/syscalls.h

2008-07-22T12:35:57+00:00

Declaring arch-dependent syscalls for x86 architecture

Signed-off-by: Jaswinder Singh

asmlinkage_protect replaces prevent_tail_call

2008-04-11T00:28:26+00:00

The prevent_tail_call() macro works around the problem of the compiler
clobbering argument words on the stack, which for asmlinkage functions
is the caller's (user's) struct pt_regs.  The tail/sibling-call
optimization is not the only way that the compiler can decide to use
stack argument words as scratch space, which we have to prevent.
Other optimizations can do it too.

Until we have new compiler support to make "asmlinkage" binding on the
compiler's own use of the stack argument frame, we have work around all
the manifestations of this issue that crop up.

More cases seem to be prevented by also keeping the incoming argument
variables live at the end of the function.  This makes their original
stack slots attractive places to leave those variables, so the compiler
tends not clobber them for something else.  It's still no guarantee, but
it handles some observed cases that prevent_tail_call() did not.

Signed-off-by: Roland McGrath 
Signed-off-by: Linus Torvalds

x86: tls prevent_tail_call

2008-02-29T17:55:39+00:00

Fix a kernel bug (vmware boot problem) reported by Tomasz Grobelny,
which occurs with certain .config variants and gccs.

The x86 TLS cleanup in commit efd1ca52d04d2f6df337a3332cee56cd60e6d4c4
made the sys_set_thread_area and sys_get_thread_area functions ripe for
tail call optimization.  If the compiler chooses to use it for them, it
can clobber the user trap frame because these are asmlinkage functions.

Reported-by: Tomasz Grobelny 
Signed-off-by: Roland McGrath 
Signed-off-by: Ingo Molnar

x86: x86 user_regset TLS

2008-01-30T12:31:52+00:00

This adds accessor functions in the user_regset style for the TLS data.

Signed-off-by: Roland McGrath 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

x86: x86 TLS desc_struct cleanup

2008-01-30T12:31:51+00:00

This cleans up the TLS code to use struct desc_struct and to separate the
encoding and installation magic from the interface wrappers.

Signed-off-by: Roland McGrath 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

x86: modify get_desc_base

2008-01-30T12:31:14+00:00

This patch makes get_desc_base() receive a struct desc_struct,
and then uses its internal fields to compute the base address.
This is done at both i386 and x86_64, and then it is moved
to common header

Signed-off-by: Glauber de Oliveira Costa 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

x86: introduce fill_ldt

2008-01-30T12:31:13+00:00

This patch introduces fill_ldt(), which populates a ldt descriptor
from a user_desc in once, instead of relying in the LDT_entry_a and
LDT_entry_b macros

Signed-off-by: Glauber de Oliveira Costa 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

x86: TLS cleanup

2008-01-30T12:30:46+00:00

This consolidates the four different places that implemented the same
encoding magic for the GDT-slot 32-bit TLS support.  The old tls32.c was
renamed and is now only slightly modified to be the shared implementation.

Signed-off-by: Roland McGrath 
Cc: Andrew Morton 
Cc: Zachary Amsden 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

x86: tls32 moved

2008-01-30T12:30:45+00:00

This renames arch/x86/ia32/tls32.c to arch/x86/kernel/tls.c, which does
nothing now but paves the way to consolidate this code for 32-bit too.

Signed-off-by: Roland McGrath 
Cc: Andrew Morton 
Cc: Zachary Amsden 
Signed-off-by: Thomas Gleixner 
Signed-off-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner