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 <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <asm/user.h>
#include <string.h>
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 <jason.wessel@windriver.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 <paulus@samba.org> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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 <bob.picco@hp.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Handle arbitrary base and length values as long as they are multiples of IO_PAGE_SIZE. Bug found by Arun Kumar Rao. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It was using an immediate _PAGE_EXEC_4U value in an 'and' instruction to perform the test. This doesn't work because the immediate field is signed 13-bit, this the mask being tested against the PTE was 0x1000 sign-extended to 32-bits instead of just plain 0x1000. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
1) The TSB lookup was not using the correct hash mask. 2) It was not aligned on a boundary equal to it's size, which is required by the sun4v Hypervisor. wasn't having it's return value checked, and that bug will be fixed up as well in a subsequent changeset. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Force Dell E520 to use the BIOS to shutdown/reboot. I have at least one report that this patch fixes shutdown/reboot problems on the Dell E520 platform. (Andi says: People can always set the boot option. It hardly seems like a critical issue needing a backport.) Signed-off-by: Tim Gardner <tim.gardner@ubuntu.com> Acked-by: Andi Kleen <ak@suse.de> Acked-by: Matt Domsch <Matt_Domsch@dell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Chuck reports that the recent fix from Andi to oprofile 6c977aad03a18019015035958c65b6729cd0574c introduces a double free. Each cpu's cpu_msrs is setup to point to cpu 0's, which causes free_msrs to free cpu 0's pointers for_each_possible_cpu. Rather than copy the pointers, do a deep copy instead. [acme@redhat.com: allocate_msrs() was using for_each_online_cpu()] Signed-off-by: Chris Wright <chrisw@sous-sol.org> Cc: Andi Kleen <ak@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Dave Jones <davej@redhat.com> Cc: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make the PTRACE_SYSEMU checking more robust. It will make sure that system call numbers are reported correctly. If there is a problem, it will disable PTRACE_SYSEMU use and use PTRACE_SYSCALL instead. This fixes a hang on boot on FC6 hosts with a broken PTRACE_SYSEMU. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> -- arch/um/os-Linux/start_up.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-)
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 <nanhai.zou@intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [chrisw: trivial backport] Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>