linux-toradex.git/arch, branch v2.6.20.19

[PATCH] UML: exports for hostfs

2007-08-25T15:24:17+00:00

Add some exports for hostfs that are required after Alberto Bertogli's
fixes for accessing unlinked host files.

Also did some style cleanups while I was here.

Signed-off-by: Jeff Dike 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

[PATCH] acpi-cpufreq: Proper ReadModifyWrite of PERF_CTL MSR

2007-08-25T15:24:12+00:00

[CPUFREQ] acpi-cpufreq: Proper ReadModifyWrite of PERF_CTL MSR

During recent acpi-cpufreq changes, writing to PERF_CTL msr
changed from RMW of entire 64 bit to RMW of low 32 bit and clearing of
upper 32 bit. Fix it back to do a proper RMW of the MSR.

Signed-off-by: Venkatesh Pallipadi 
Signed-off-by: Dave Jones 
Cc: Chuck Ebbert 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

[PATCH] Fix sparc32 udelay() rounding errors.

2007-08-25T15:24:01+00:00

[SPARC32]: Fix rounding errors in ndelay/udelay implementation.

__ndelay and __udelay have not been delayung >= specified time.
The problem with __ndelay has been tacked down to the rounding of the
multiplier constant. By changing this, delays > app 18us are correctly
calculated.
The problem with __udelay has also been tracked down to rounding issues.
Changing the multiplier constant (to match that used in sparc64) corrects
for large delays and adding in a rounding constant corrects for trunctaion
errors in the claculations.
Many short delays will return without looping. This is not an error as there
is the fixed delay of doing all the maths to calculate the loop count.

Signed-off-by: Mark Fortescue 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

[PATCH] Fix sparc32 memset()

2007-08-25T15:24:00+00:00

[SPARC32]: Fix bug in sparc optimized memset.

Sparc optimized memset (arch/sparc/lib/memset.S) does not fill last
byte of the memory area, if area size is less than 8 bytes and start
address is not word (4-bytes) aligned.

Here is code chunk where bug located:
/* %o0 - memory address, %o1 - size, %g3 - value */
8:
     add    %o0, 1, %o0
    subcc    %o1, 1, %o1
    bne,a    8b
     stb %g3, [%o0 - 1]

This code should write byte every loop iteration, but last time delay
instruction stb is not executed because branch instruction sets
"annul" bit.

Patch replaces bne,a by bne instruction.

Error can be reproduced by simple kernel module:

--------------------
#include 
#include 
#include 
#include 
#include 

static void do_memset(void **p, int size)
{
        memset(p, 0x00, size);
}

static int __init memset_test_init(void)
{
    char fooc[8];
    int *fooi;
    memset(fooc, 0xba, sizeof(fooc));

    do_memset((void**)(fooc + 3), 1);

    fooi = (int*) fooc;
    printk("%08X %08X\n", fooi[0], fooi[1]);

    return -1;
}

static void __exit memset_test_cleanup(void)
{
    return;
}

module_init(memset_test_init);
module_exit(memset_test_cleanup);

MODULE_LICENSE("GPL");
EXPORT_NO_SYMBOLS;
------------------------

Signed-off-by: Alexander Shmelev 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

[PATCH] Sparc64 bootup assembler bug

2007-08-25T15:24:00+00:00

[SPARC64]: Fix two year old bug in early bootup asm.

We try to fetch the CIF entry pointer from %o4, but that
can get clobbered by the early OBP calls.  It is saved
in %l7 already, so actually this "mov %o4, %l7" can just
be completely removed with no other changes.

Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Willy Tarreau

[PATCH] i386: fix infinite loop with singlestep int80 syscalls

2007-08-15T08:02:35+00:00

The commit 635cf99a80f4ebee59d70eb64bb85ce829e4591f introduced a
regression.  Executing a ptrace single step after certain int80
accesses will infinitely loop and never advance the PC.

The TIF_SINGLESTEP check should be done on the return from the syscall
and not before it.

The new test case is below:

/* Test whether singlestep through an int80 syscall works.
 */
#define _GNU_SOURCE
#include 
#include 
#include 
#include 
#include 
#include 
#include 
#include 

static int child, status;
static struct user_regs_struct regs;

static void do_child()
{
	char str[80] = "child: int80 test\n";

	ptrace(PTRACE_TRACEME, 0, 0, 0);
	kill(getpid(), SIGUSR1);
	write(fileno(stdout),str,strlen(str));
	asm ("int $0x80" : : "a" (20)); /* getpid */
}

static void do_parent()
{
	unsigned long eip, expected = 0;
again:
	waitpid(child, &status, 0);
	if (WIFEXITED(status) || WIFSIGNALED(status))
		return;

	if (WIFSTOPPED(status)) {
		ptrace(PTRACE_GETREGS, child, 0, ®s);
		eip = regs.eip;
		if (expected)
			fprintf(stderr, "child stop @ %08lx, expected %08lx %s\n",
					eip, expected,
					eip == expected ? "" : " <== ERROR");

		if (*(unsigned short *)eip == 0x80cd) {
			fprintf(stderr, "int 0x80 at %08x\n", (unsigned int)eip);
			expected = eip + 2;
		} else
			expected = 0;

		ptrace(PTRACE_SINGLESTEP, child, NULL, NULL);
	}
	goto again;
}

int main(int argc, char * const argv[])
{
	child = fork();
	if (child)
		do_parent();
	else
		do_child();
	return 0;
}

Signed-off-by: Jason Wessel 
Cc: Jeremy Fitzhardinge 
Cc: Chuck Ebbert 
Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

[PATCH] POWERPC: Fix subtle FP state corruption bug in signal return on SMP

2007-08-15T08:02:32+00:00

This fixes a bug which can cause corruption of the floating-point state
on return from a signal handler.  If we have a signal handler that has
used the floating-point registers, and it happens to context-switch to
another task while copying the interrupted floating-point state from the
user stack into the thread struct (e.g. because of a page fault, or
because it gets preempted), the context switch code will think that the
FP registers contain valid FP state that needs to be copied into the
thread_struct, and will thus overwrite the values that the signal return
code has put into the thread_struct.

This can occur because we clear the MSR bits that indicate the presence
of valid FP state after copying the state into the thread_struct.  To fix
this we just move the clearing of the MSR bits to before the copy.  A
similar potential problem also occurs with the Altivec state, and this
fixes that in the same way.

Signed-off-by: Paul Mackerras 
Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

[PATCH] sparsemem: fix oops in x86_64 show_mem

2007-08-15T08:02:25+00:00

We aren't sampling for holes in memory. Thus we encounter a section hole with
empty section map pointer for SPARSEMEM and OOPs for show_mem. This issue
has been seen in 2.6.21, current git and current mm. This patch is for
2.6.21 stable. It was tested against sparsemem.

Previous to commit f0a5a58aa812b31fd9f197c4ba48245942364eae memory_present
was called for node_start_pfn to node_end_pfn. This would cover the hole(s)
with reserved pages and valid sections. Most SPARSEMEM supported arches
do a pfn_valid check in show_mem before computing the page structure address.

This issue was brought to my attention on IRC by Arnaldo Carvalho de Melo at
acme@redhat.com. Thanks to Arnaldo for testing.

Signed-off-by: Bob Picco 
Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

[PATCH] x86_64: allocate sparsemem memmap above 4G

2007-08-15T08:02:24+00:00

On systems with huge amount of physical memory, VFS cache and memory memmap
may eat all available system memory under 4G, then the system may fail to
allocate swiotlb bounce buffer.

There was a fix for this issue in arch/x86_64/mm/numa.c, but that fix dose
not cover sparsemem model.

This patch add fix to sparsemem model by first try to allocate memmap above
4G.

Signed-off-by: Zou Nan hai 
Acked-by: Suresh Siddha 
Cc: Andi Kleen 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
[chrisw: trivial backport]
Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

[PATCH] i386: Fix K8/core2 oprofile on multiple CPUs

2007-08-15T08:02:20+00:00

Only try to allocate MSRs once instead of for every CPU.

This assumes the MSRs are the same on all CPUs which is currently
true. P4-HT is a special case for different SMT threads, but the code
always saves/restores all MSRs so it works identical.

Signed-off-by: Andi Kleen 
Signed-off-by: Linus Torvalds 
Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman