Commit Graph

8 Commits

Author SHA1 Message Date
Chris Lalancette 2c75910f1a x86: Make sure get_user_desc() doesn't sign extend.
The current implementation of get_user_desc() sign extends the return
value because of integer promotion rules.  For the most part, this
doesn't matter, because the top bit of base2 is usually 0.  If, however,
that bit is 1, then the entire value will be 0xffff...  which is
probably not what the caller intended.

This patch casts the entire thing to unsigned before returning, which
generates almost the same assembly as the current code but replaces the
final "cltq" (sign extend) with a "mov %eax %eax" (zero-extend).  This
fixes booting certain guests under KVM.

Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-05 13:22:18 -08:00
Akinobu Mita 57594742a2 x86: Introduce set_desc_base() and set_desc_limit()
Rename set_base()/set_limit to set_desc_base()/set_desc_limit()
and rewrite them in C. These are naturally introduced by the
idea of get_desc_base()/get_desc_limit().

The conversion actually found the bug in apm_32.c:
bad_bios_desc is written at run-time, but it is defined const
variable.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
LKML-Reference: <20090718151105.GC11294@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-07-19 18:27:52 +02:00
Alexander van Heukelum bc3f5d3dbd x86: de-assembler-ize asm/desc.h
asm/desc.h is included in three assembly files, but the only macro
it defines, GET_DESC_BASE, is never used. This patch removes the
includes, removes the macro GET_DESC_BASE and the ASSEMBLY guard
from asm/desc.h.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-06-17 21:35:10 -07:00
David Howells 9b8de7479d FRV: Fix the section attribute on UP DECLARE_PER_CPU()
In non-SMP mode, the variable section attribute specified by DECLARE_PER_CPU()
does not agree with that specified by DEFINE_PER_CPU().  This means that
architectures that have a small data section references relative to a base
register may throw up linkage errors due to too great a displacement between
where the base register points and the per-CPU variable.

On FRV, the .h declaration says that the variable is in the .sdata section, but
the .c definition says it's actually in the .data section.  The linker throws
up the following errors:

kernel/built-in.o: In function `release_task':
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o

To fix this, DECLARE_PER_CPU() should simply apply the same section attribute
as does DEFINE_PER_CPU().  However, this is made slightly more complex by
virtue of the fact that there are several variants on DEFINE, so these need to
be matched by variants on DECLARE.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:39:59 -07:00
Jaswinder Singh Rajput 8229d75438 x86: cpu architecture debug code, build fix, cleanup
move store_ldt outside the CONFIG_PARAVIRT section and
also clean up the code a bit.

Signed-off-by: Jaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-03-11 14:52:03 +01:00
Yinghai Lu b77b881f21 x86: fix lguest used_vectors breakage, -v2
Impact: fix lguest, clean up

32-bit lguest used used_vectors to record vectors, but that model of
allocating vectors changed and got broken, after we changed vector
allocation to a per_cpu array.

Try enable that for 64bit, and the array is used for all vectors that
are not managed by vector_irq per_cpu array.

Also kill system_vectors[], that is now a duplication of the
used_vectors bitmap.

[ merged in cpus4096 due to io_apic.c cpumask changes. ]
[ -v2, fix build failure ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-12-23 22:37:28 +01:00
H. Peter Anvin 1965aae3c9 x86: Fix ASM_X86__ header guards
Change header guards named "ASM_X86__*" to "_ASM_X86_*" since:

a. the double underscore is ugly and pointless.
b. no leading underscore violates namespace constraints.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:23 -07:00
Al Viro bb8985586b x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2008-10-22 22:55:20 -07:00