Impact: add ability to trace modules on 32 bit PowerPC
This patch performs the necessary trampoline calls to handle
modules with dynamic ftrace on 32 bit PowerPC.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: Allow 64 bit PowerPC to trace modules with dynamic ftrace
This adds code to handle the PPC64 module trampolines, and allows for
PPC64 to use dynamic ftrace.
Thanks to Paul Mackerras for these updates:
- fix the mod and rec->arch.mod NULL checks.
- fix to is_bl_op compare.
Thanks to Milton Miller for:
- finding the nasty race with using two nops, and recommending
instead that I use a branch 8 forward.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: use cleaner probe_kernel API over assembly
Using probe_kernel_read/write interface is a much cleaner approach
than the current assembly version.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: update to PowerPC ftrace arch API
This patch converts PowerPC to use the new dynamic ftrace arch API.
Thanks to Paul Mackennas for pointing out the mistakes of my original
test_24bit_addr function.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: fix for irq off latency tracer
When idle is called, interrupts are disabled, but the idle function
will still wake up on an interrupt. The problem is that the interrupt
disabled latency tracer will take this call to idle as a latency.
This patch disables the latency tracing when going into idle.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Annotate xsave_cntxt_init() as "can be called outside of __init".
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix incorrect __init annotation
This patch removes the following section mismatch warning. A patch set
was send previously (http://lkml.org/lkml/2008/11/10/407). But
introduce some other problem, reported by Rufus
(http://lkml.org/lkml/2008/11/11/46). Then Ingo Molnar suggest that,
it's best to remove __init from xsave_cntxt_init(void). Which is the
second patch in this series. Now, this one removes the following
warning.
WARNING: arch/x86/kernel/built-in.o(.cpuinit.text+0x2237): Section
mismatch in reference from the function cpu_init() to the function
.init.text:init_thread_xstate()
The function __cpuinit cpu_init() references
a function __init init_thread_xstate().
If init_thread_xstate is only used by cpu_init then
annotate init_thread_xstate with a matching annotation.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86/numa' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: make NUMA on 32-bit depend on EXPERIMENTAL again
x86, hibernate: fix breakage on x86_32 with CONFIG_NUMA set
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: more general identifier for Phoenix BIOS
AMD IOMMU: check for next_bit also in unmapped area
AMD IOMMU: fix fullflush comparison length
AMD IOMMU: enable device isolation per default
AMD IOMMU: add parameter to disable device isolation
x86, PEBS/DS: fix code flow in ds_request()
x86: add rdtsc barrier to TSC sync check
xen: fix scrub_page()
x86: fix es7000 compiling
x86, bts: fix unlock problem in ds.c
x86, voyager: fix smp generic helper voyager breakage
x86: move iomap.h to the new include location
This adds the sparc syscall hookups.
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce a new accept4() system call. The addition of this system call
matches analogous changes in 2.6.27 (dup3(), evenfd2(), signalfd4(),
inotify_init1(), epoll_create1(), pipe2()) which added new system calls
that differed from analogous traditional system calls in adding a flags
argument that can be used to access additional functionality.
The accept4() system call is exactly the same as accept(), except that
it adds a flags bit-mask argument. Two flags are initially implemented.
(Most of the new system calls in 2.6.27 also had both of these flags.)
SOCK_CLOEXEC causes the close-on-exec (FD_CLOEXEC) flag to be enabled
for the new file descriptor returned by accept4(). This is a useful
security feature to avoid leaking information in a multithreaded
program where one thread is doing an accept() at the same time as
another thread is doing a fork() plus exec(). More details here:
http://udrepper.livejournal.com/20407.html "Secure File Descriptor Handling",
Ulrich Drepper).
The other flag is SOCK_NONBLOCK, which causes the O_NONBLOCK flag
to be enabled on the new open file description created by accept4().
(This flag is merely a convenience, saving the use of additional calls
fcntl(F_GETFL) and fcntl (F_SETFL) to achieve the same result.
Here's a test program. Works on x86-32. Should work on x86-64, but
I (mtk) don't have a system to hand to test with.
It tests accept4() with each of the four possible combinations of
SOCK_CLOEXEC and SOCK_NONBLOCK set/clear in 'flags', and verifies
that the appropriate flags are set on the file descriptor/open file
description returned by accept4().
I tested Ulrich's patch in this thread by applying against 2.6.28-rc2,
and it passes according to my test program.
/* test_accept4.c
Copyright (C) 2008, Linux Foundation, written by Michael Kerrisk
<mtk.manpages@gmail.com>
Licensed under the GNU GPLv2 or later.
*/
#define _GNU_SOURCE
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdlib.h>
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#define PORT_NUM 33333
#define die(msg) do { perror(msg); exit(EXIT_FAILURE); } while (0)
/**********************************************************************/
/* The following is what we need until glibc gets a wrapper for
accept4() */
/* Flags for socket(), socketpair(), accept4() */
#ifndef SOCK_CLOEXEC
#define SOCK_CLOEXEC O_CLOEXEC
#endif
#ifndef SOCK_NONBLOCK
#define SOCK_NONBLOCK O_NONBLOCK
#endif
#ifdef __x86_64__
#define SYS_accept4 288
#elif __i386__
#define USE_SOCKETCALL 1
#define SYS_ACCEPT4 18
#else
#error "Sorry -- don't know the syscall # on this architecture"
#endif
static int
accept4(int fd, struct sockaddr *sockaddr, socklen_t *addrlen, int flags)
{
printf("Calling accept4(): flags = %x", flags);
if (flags != 0) {
printf(" (");
if (flags & SOCK_CLOEXEC)
printf("SOCK_CLOEXEC");
if ((flags & SOCK_CLOEXEC) && (flags & SOCK_NONBLOCK))
printf(" ");
if (flags & SOCK_NONBLOCK)
printf("SOCK_NONBLOCK");
printf(")");
}
printf("\n");
#if USE_SOCKETCALL
long args[6];
args[0] = fd;
args[1] = (long) sockaddr;
args[2] = (long) addrlen;
args[3] = flags;
return syscall(SYS_socketcall, SYS_ACCEPT4, args);
#else
return syscall(SYS_accept4, fd, sockaddr, addrlen, flags);
#endif
}
/**********************************************************************/
static int
do_test(int lfd, struct sockaddr_in *conn_addr,
int closeonexec_flag, int nonblock_flag)
{
int connfd, acceptfd;
int fdf, flf, fdf_pass, flf_pass;
struct sockaddr_in claddr;
socklen_t addrlen;
printf("=======================================\n");
connfd = socket(AF_INET, SOCK_STREAM, 0);
if (connfd == -1)
die("socket");
if (connect(connfd, (struct sockaddr *) conn_addr,
sizeof(struct sockaddr_in)) == -1)
die("connect");
addrlen = sizeof(struct sockaddr_in);
acceptfd = accept4(lfd, (struct sockaddr *) &claddr, &addrlen,
closeonexec_flag | nonblock_flag);
if (acceptfd == -1) {
perror("accept4()");
close(connfd);
return 0;
}
fdf = fcntl(acceptfd, F_GETFD);
if (fdf == -1)
die("fcntl:F_GETFD");
fdf_pass = ((fdf & FD_CLOEXEC) != 0) ==
((closeonexec_flag & SOCK_CLOEXEC) != 0);
printf("Close-on-exec flag is %sset (%s); ",
(fdf & FD_CLOEXEC) ? "" : "not ",
fdf_pass ? "OK" : "failed");
flf = fcntl(acceptfd, F_GETFL);
if (flf == -1)
die("fcntl:F_GETFD");
flf_pass = ((flf & O_NONBLOCK) != 0) ==
((nonblock_flag & SOCK_NONBLOCK) !=0);
printf("nonblock flag is %sset (%s)\n",
(flf & O_NONBLOCK) ? "" : "not ",
flf_pass ? "OK" : "failed");
close(acceptfd);
close(connfd);
printf("Test result: %s\n", (fdf_pass && flf_pass) ? "PASS" : "FAIL");
return fdf_pass && flf_pass;
}
static int
create_listening_socket(int port_num)
{
struct sockaddr_in svaddr;
int lfd;
int optval;
memset(&svaddr, 0, sizeof(struct sockaddr_in));
svaddr.sin_family = AF_INET;
svaddr.sin_addr.s_addr = htonl(INADDR_ANY);
svaddr.sin_port = htons(port_num);
lfd = socket(AF_INET, SOCK_STREAM, 0);
if (lfd == -1)
die("socket");
optval = 1;
if (setsockopt(lfd, SOL_SOCKET, SO_REUSEADDR, &optval,
sizeof(optval)) == -1)
die("setsockopt");
if (bind(lfd, (struct sockaddr *) &svaddr,
sizeof(struct sockaddr_in)) == -1)
die("bind");
if (listen(lfd, 5) == -1)
die("listen");
return lfd;
}
int
main(int argc, char *argv[])
{
struct sockaddr_in conn_addr;
int lfd;
int port_num;
int passed;
passed = 1;
port_num = (argc > 1) ? atoi(argv[1]) : PORT_NUM;
memset(&conn_addr, 0, sizeof(struct sockaddr_in));
conn_addr.sin_family = AF_INET;
conn_addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
conn_addr.sin_port = htons(port_num);
lfd = create_listening_socket(port_num);
if (!do_test(lfd, &conn_addr, 0, 0))
passed = 0;
if (!do_test(lfd, &conn_addr, SOCK_CLOEXEC, 0))
passed = 0;
if (!do_test(lfd, &conn_addr, 0, SOCK_NONBLOCK))
passed = 0;
if (!do_test(lfd, &conn_addr, SOCK_CLOEXEC, SOCK_NONBLOCK))
passed = 0;
close(lfd);
exit(passed ? EXIT_SUCCESS : EXIT_FAILURE);
}
[mtk.manpages@gmail.com: rewrote changelog, updated test program]
Signed-off-by: Ulrich Drepper <drepper@redhat.com>
Tested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <linux-api@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__copy_from_user() will return invalid value 16 when it fails to
access user space and the size is 10.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Dell Optiplex 330 appears to hang on reboot. This is resolved by adding
a quirk to set bios reboot.
Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>
Signed-off-by: Steve Conklin <steve.conklin@canonical.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: widen the reach of the low-memory-protect DMI quirk
Phoenix BIOSes variously identify their vendor as "Phoenix Technologies,
LTD" or "Phoenix Technologies LTD" (without the comma.)
This patch makes the identification string in the bad_bios_dmi_table
more general (following a suggestion by Ingo Molnar), so that both
versions are handled.
Again, the patched file compiles cleanly and the patch has been tested
successfully on my machine.
Signed-off-by: Philipp Kohlbecher <xt28@gmx.de>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: makes device isolation the default for AMD IOMMU
Some device drivers showed double-free bugs of DMA memory while testing
them with AMD IOMMU. If all devices share the same protection domain
this can lead to data corruption and data loss. Prevent this by putting
each device into its own protection domain per default.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
this compiler warning:
arch/x86/kernel/ds.c: In function 'ds_request':
arch/x86/kernel/ds.c:368: warning: 'context' may be used uninitialized in this function
Shows that the code flow in ds_request() is buggy - it goes into
the unlock+release-context path even when the context is not allocated
yet.
First allocate the context, then do the other checks.
Also, take care with GFP allocations under the ds_lock spinlock.
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: help to find the better depth of trace
We decided to arbitrary define the depth of function return trace as
"20". Perhaps this is not enough. To help finding an optimal depth, we
measure now the overrun: the number of functions that have been missed
for the current thread. By default this is not displayed, we have to
do set a particular flag on the return tracer: echo overrun >
/debug/tracing/trace_options And the overrun will be printed on the
right.
As the trace shows below, the current 20 depth is not enough.
update_wall_time+0x37f/0x8c0 -> update_xtime_cache (345 ns) (Overruns: 2838)
update_wall_time+0x384/0x8c0 -> clocksource_get_next (1141 ns) (Overruns: 2838)
do_timer+0x23/0x100 -> update_wall_time (3882 ns) (Overruns: 2838)
tick_do_update_jiffies64+0xbf/0x160 -> do_timer (5339 ns) (Overruns: 2838)
tick_sched_timer+0x6a/0xf0 -> tick_do_update_jiffies64 (7209 ns) (Overruns: 2838)
vgacon_set_cursor_size+0x98/0x120 -> native_io_delay (2613 ns) (Overruns: 274)
vgacon_cursor+0x16e/0x1d0 -> vgacon_set_cursor_size (33151 ns) (Overruns: 274)
set_cursor+0x5f/0x80 -> vgacon_cursor (36432 ns) (Overruns: 274)
con_flush_chars+0x34/0x40 -> set_cursor (38790 ns) (Overruns: 274)
release_console_sem+0x1ec/0x230 -> up (721 ns) (Overruns: 274)
release_console_sem+0x225/0x230 -> wake_up_klogd (316 ns) (Overruns: 274)
con_flush_chars+0x39/0x40 -> release_console_sem (2996 ns) (Overruns: 274)
con_write+0x22/0x30 -> con_flush_chars (46067 ns) (Overruns: 274)
n_tty_write+0x1cc/0x360 -> con_write (292670 ns) (Overruns: 274)
smp_apic_timer_interrupt+0x2a/0x90 -> native_apic_mem_write (330 ns) (Overruns: 274)
irq_enter+0x17/0x70 -> idle_cpu (413 ns) (Overruns: 274)
smp_apic_timer_interrupt+0x2f/0x90 -> irq_enter (1525 ns) (Overruns: 274)
ktime_get_ts+0x40/0x70 -> getnstimeofday (465 ns) (Overruns: 274)
ktime_get_ts+0x60/0x70 -> set_normalized_timespec (436 ns) (Overruns: 274)
ktime_get+0x16/0x30 -> ktime_get_ts (2501 ns) (Overruns: 274)
hrtimer_interrupt+0x77/0x1a0 -> ktime_get (3439 ns) (Overruns: 274)
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
dma_mapping_error is an actual function, so fix broken define with a
real inline stub
Signed-off-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Impact: fix incorrectly marked unstable TSC clock
Patch (commit 0d12cdd "sched: improve sched_clock() performance") has
a regression on one of the test systems here.
With the patch, I see:
checking TSC synchronization [CPU#0 -> CPU#1]:
Measured 28 cycles TSC warp between CPUs, turning off TSC clock.
Marking TSC unstable due to check_tsc_sync_source failed
Whereas, without the patch syncs pass fine on all CPUs:
checking TSC synchronization [CPU#0 -> CPU#1]: passed.
Due to this, TSC is marked unstable, when it is not actually unstable.
This is because syncs in check_tsc_wrap() goes away due to this commit.
As per the discussion on this thread, correct way to fix this is to add
explicit syncs as below?
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
reset_value was changed from long to u64 in commit
b991702884 (oprofile: Implement Intel
architectural perfmon support)
But dynamic allocation of this array use a wrong type (long instead of
u64)
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Robert Richter <robert.richter@amd.com>
This patch makes do_hw_reset the default reboot behavior when nothing
else matches. This restores reboot functionality on gumstix basix
devices where reboot=cold is the default boot argument.
Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Impact: fix es7000 build
CC arch/x86/kernel/es7000_32.o
arch/x86/kernel/es7000_32.c: In function find_unisys_acpi_oem_table:
arch/x86/kernel/es7000_32.c:255: error: implicit declaration of function acpi_get_table_with_size
arch/x86/kernel/es7000_32.c:261: error: implicit declaration of function early_acpi_os_unmap_memory
arch/x86/kernel/es7000_32.c: In function unmap_unisys_acpi_oem_table:
arch/x86/kernel/es7000_32.c:277: error: implicit declaration of function __acpi_unmap_table
make[1]: *** [arch/x86/kernel/es7000_32.o] Error 1
we applied one patch out of order...
| commit a73aaedd95
| Author: Yinghai Lu <yhlu.kernel@gmail.com>
| Date: Sun Sep 14 02:33:14 2008 -0700
|
| x86: check dsdt before find oem table for es7000, v2
|
| v2: use __acpi_unmap_table()
that patch need:
x86: use early_ioremap in __acpi_map_table
x86: always explicitly map acpi memory
acpi: remove final __acpi_map_table mapping before setting acpi_gbl_permanent_mmap
acpi/x86: introduce __apci_map_table, v4
submitted to the ACPI tree but not upstream yet.
fix it until those patches applied, need to revert this one
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The original incorrect configuration caused GPIO79_nCS_3 being overriden,
thus resulted in the NAND flash not being detected. The real PSKTSEL pin
is on GPIO104 instead of GPIO79.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Fix a problem where ds_request() returned an error without releasing the
ds lock.
Reported-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Markus Metzger <markus.t.metzger@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch adds the support for dynamic tracing on the function return tracer.
The whole difference with normal dynamic function tracing is that we don't need
to hook on a particular callback. The only pro that we want is to nop or set
dynamically the calls to ftrace_caller (which is ftrace_return_caller here).
Some security checks ensure that we are not trying to launch dynamic tracing for
return tracing while normal function tracing is already running.
An example of trace with getnstimeofday set as a filter:
ktime_get_ts+0x22/0x50 -> getnstimeofday (2283 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1396 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1825 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1426 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1464 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1524 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1382 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1434 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1464 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1502 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1404 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1397 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1051 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1314 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1344 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1163 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1390 ns)
ktime_get_ts+0x22/0x50 -> getnstimeofday (1374 ns)
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix possible race condition in ftrace function return tracer
This fixes a possible race condition if index incrementation
is not immediately flushed in memory.
Thanks for Andi Kleen and Steven Rostedt for pointing out this issue
and give me this solution.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: allow archs more flexibility on dynamic ftrace implementations
Dynamic ftrace has largly been developed on x86. Since x86 does not
have the same limitations as other architectures, the ftrace interaction
between the generic code and the architecture specific code was not
flexible enough to handle some of the issues that other architectures
have.
Most notably, module trampolines. Due to the limited branch distance
that archs make in calling kernel core code from modules, the module
load code must create a trampoline to jump to what will make the
larger jump into core kernel code.
The problem arises when this happens to a call to mcount. Ftrace checks
all code before modifying it and makes sure the current code is what
it expects. Right now, there is not enough information to handle modifying
module trampolines.
This patch changes the API between generic dynamic ftrace code and
the arch dependent code. There is now two functions for modifying code:
ftrace_make_nop(mod, rec, addr) - convert the code at rec->ip into
a nop, where the original text is calling addr. (mod is the
module struct if called by module init)
ftrace_make_caller(rec, addr) - convert the code rec->ip that should
be a nop into a caller to addr.
The record "rec" now has a new field called "arch" where the architecture
can add any special attributes to each call site record.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'sh/for-2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
serial: sh-sci: Reorder the SCxTDR write after the TDxE clear.
sh: __copy_user function can corrupt the stack in case of exception
sh: Fixed the TMU0 reload value on resume
sh: Don't factor in PAGE_OFFSET for valid_phys_addr_range() check.
sh: early printk port type fix
i2c: fix i2c-sh_mobile rx underrun
sh: Provide a sane valid_phys_addr_range() to prevent TLB reset with PMB.
usb: r8a66597-hcd: fix wrong data access in SuperH on-chip USB
fix sci type for SH7723
serial: sh-sci: fix cannot work SH7723 SCIFA
sh: Handle fixmap TLB eviction more coherently.
This reverts commit e51af66308, which was
wrongly hoovered up and submitted about a month after a better fix had
already been merged.
The better fix is commit cbda1ba898
("PCI/iommu: blacklist DMAR on Intel G31/G33 chipsets"), where we do
this blacklisting based on the DMI identification for the offending
motherboard, since sometimes this chipset (or at least a chipset with
the same PCI ID) apparently _does_ actually have an IOMMU.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
commit 69961c3752 ("[PATCH] m68k/Atari:
Interrupt updates") added a BUG_ON() with an incorrect upper bound
comparison, which causes an early crash on VME boards, where IRQ_USER is
8, cnt is 192 and NR_IRQS is 200.
Reported-by: Stephen N Chivers <schivers@csc.com.au>
Tested-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The uname system call for 64 bit compares current->personality without
masking the upper 16 bits. If e.g. READ_IMPLIES_EXEC is set the result
of a uname system call will always be s390x even if the process uses
the s390 personality.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
cpu_coregroup_map used to grab a mutex on s390 since it was only
called from process context.
Since c7c22e4d5c "block: add support
for IO CPU affinity" this is not true anymore.
It now also gets called from softirq context.
To prevent possible deadlocks change this in architecture code and
use a spinlock instead of a mutex.
Cc: stable@kernel.org
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
With CONFIG_IRQSOFF_TRACER the trace_hardirqs_off() function includes
a call to __builtin_return_address(1). But we calltrace_hardirqs_off()
from early entry code. There we have just a single stack frame.
So this results in a kernel stack backchain walk that would walk beyond
the kernel stack. Following the NULL terminated backchain this results
in a lowcore read access.
To fix this we simply call trace_hardirqs_off_caller() and pass the
current instruction pointer.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Disable tracing on idle psw. Otherwise it would give us huge
preempt off times for idle. Which is rather pointless.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/kernel/built-in.o: In function `cleanup_io_leave_insn':
mem_detect.c:(.text+0x10592): undefined reference to `lockdep_sys_exit'
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
add_active_range() expects start_pfn + size as end_pfn value, i.e. not
the pfn of the last page frame but the one behind that.
We used the pfn of the last page frame so far, which can lead to a
BUG_ON in move_freepages(), when the kernelcore parameter is specified
(page_zone(start_page) != page_zone(end_page)).
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Commit 2d3854a37e ("cpumask: introduce new
API, without changing anything") introduced a build breakage on parisc.
This trivial patch fixes it.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Kyle Mc Martin <kyle@hera.kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
FLASH_* and EPROM_* constants are unused, and clash with drivers:
drivers/atm/ambassador.h:257:1: warning: "FLASH_BASE" redefined
drivers/atm/ambassador.h:258:1: warning: "FLASH_SIZE" redefined
drivers/atm/iphase.h:332:1: warning: "EPROM_SIZE" redefined
so remove them.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/mm/dma-mapping.c: In function `dma_sync_sg_for_cpu':
arch/arm/mm/dma-mapping.c:588: warning: statement with no effect
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Under qemu there is a race between the TDxE read-and-clear and the SCxTDR
write. While on hardware it can be gauranteed that the read-and-clear
will happen prior to the character being written out, no such assumption
can be made under emulation. As this path happens with IRQs off and the
hardware itself doesn't care about the ordering, move the SCxTDR write
until after the read-and-clear.
Signed-off-by: Vladimir Prus <vladimir@codesourcery.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The __copy_user function can corrupt the stack in the case of a
non-trivial length of data, and either of the first two move instructions
cause an exception. This is because the fixup for these two instructions
is mapped to the no_pop case, but these instructions execute after the
stack is pushed.
This change creates an explicit NO_POP exception mapping macro, and uses
it for the two instructions executed in the trivial case where no stack
pushes occur.
More information at ST Linux bugzilla:
https://bugzilla.stlinux.com/show_bug.cgi?id=4824
Signed-off-by: Dylan Reid <dylan_reid@bose.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes the TMU0 interrupt frequency on suspend/resume.
During the resume the kernel reprograms the TMU0.ClockEvent mode
but if the mode is periodic than the TMU0.TCOR is updated with
a random wrong value without taking care latest valid saved value.
There was no problem with No_HZ system where TMU0.TCOR isn't used.
Signed-off-by: Francesco M. Virlinzi <francesco.virlinzi@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes tty compile warnings as sugested by Alan Cox:
CC drivers/char/n_tty.o
drivers/char/n_tty.c: In function normal_poll:
drivers/char/n_tty.c:1555: warning: array subscript is above array bounds
drivers/char/n_tty.c:1564: warning: array subscript is above array bounds
drivers/char/n_tty.c: In function read_chan:
drivers/char/n_tty.c:1269: warning: array subscript is above array bounds
CC drivers/char/tty_ioctl.o
drivers/char/tty_ioctl.c: In function set_termios:
drivers/char/tty_ioctl.c:533: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:537: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c: In function tty_mode_ioctl:
drivers/char/tty_ioctl.c:662: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:892: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:896: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:577: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:928: warning: array subscript is above array
bounds
drivers/char/tty_ioctl.c:934: warning: array subscript is above array
bounds
Signed-off-by: Robert Reif <reif@earthlink.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
My previous patch to make CONFIG_NUMA on x86_32 depend on BROKEN
turned out to be unnecessary, after all, since the source of the
hibernation vs CONFIG_NUMA problem turned out to be the fact that
we didn't take the NUMA KVA remapping into account in the
hibernation code.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix crash during hibernation on 32-bit NUMA
The NUMA code on x86_32 creates special memory mapping that allows
each node's pgdat to be located in this node's memory. For this
purpose it allocates a memory area at the end of each node's memory
and maps this area so that it is accessible with virtual addresses
belonging to low memory. As a result, if there is high memory,
these NUMA-allocated areas are physically located in high memory,
although they are mapped to low memory addresses.
Our hibernation code does not take that into account and for this
reason hibernation fails on all x86_32 systems with CONFIG_NUMA=y and
with high memory present. Fix this by adding a special mapping for
the NUMA-allocated memory areas to the temporary page tables created
during the last phase of resume.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: Optimize a bit the function return tracer
This patch changes the calling convention of prepare_ftrace_return to
pass its arguments by register. This will optimize it a bit and
prepare it to support dynamic tracing.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: remove spinlocks and irq disabling in function return tracer.
I've tried to figure out all of the race condition that could happen
when the tracer pushes or pops a return address trace to/from the
current thread_info.
Theory:
_ One thread can only execute on one cpu at a time. So this code
doesn't need to be SMP-safe. Just drop the spinlock.
_ The only race could happen between the current thread and an
interrupt. If an interrupt is raised, it will increase the index of
the return stack storage and then execute until the end of the
tracing to finally free the index it used. We don't need to disable
irqs.
This is theorical. In practice, I've tested it with a two-core SMP and
had no problem at all. Perhaps -tip testing could confirm it.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: name change of unlikely tracer and profiler
Ingo Molnar suggested changing the config from UNLIKELY_PROFILE
to BRANCH_PROFILING. I never did like the "unlikely" name so I
went one step farther, and renamed all the unlikely configurations
to a "BRANCH" variant.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()
iop-adma: use iop_paranoia() for debug BUG_ONs
iop-adma: add a dummy read to flush next descriptor update
Don't do misalignment handling for userspace misalignment faults: just
generate an appropriate SIGBUS instead.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Don't handle the misaligned loading and storing of the SP register as in C code
that's most certainly a compiler bug.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Support misalignment handling for instructions that have kernel SP-based
address operands, including fixing those that include IMM8 or IMM16
displacements.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix misalignment handling for an address calculated from the sum of two
registers.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Correctly handle misalignment in MOV instructions with postinc-with-immediate
addressing mode operands. In these, the immediate value is the increment to
be applied the address register, not the displacement to the address.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Perform misalignment fixups of the MOV_Lcc instructions (move postinc memory
to register and conditionally loop).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Allow misalignment fixup in interrupt handling in the MN10300 arch.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix misalignment handling of operands with register postincrement addressing.
The flag to indicate that postincrement is required should not be interpreted
as an specification of a value to be added to the address.
Also add BUGs to catch unimplemented parameter markings in the opcodes table.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extract the displacement from an MN10300 instruction correctly in the
misalignment fixup handler.
The code should extract the displacement in LSB order, not MSB order.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add further misalignment fixup support to the MN10300 arch, notably for ABS32
and SP+disp addressing.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up the MN10300 misalignment handler a little by:
(1) Use ilog2() rather than doing implementing log2() locally.
(2) Make format_tbl[] const and static.
(3) Making the debugging prints more consistent.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: Fix pit memory leak if unable to allocate irq source id
KVM: ia64: fix vmm_spin_{un}lock for !CONFIG_SMP
KVM: VMX: Set IGMT bit in EPT entry
KVM: Require the PCI subsystem
x86: KVM guest: fix section mismatch warning in kvmclock.c
KVM: ia64: Use guest signal mask when blocking
KVM: MMU: increase per-vcpu rmap cache alloc size
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (47 commits)
ACPI: pci_link: remove acpi_irq_balance_set() interface
fujitsu-laptop: Add DMI callback for Lifebook S6420
ACPI: EC: Don't do transaction from GPE handler in poll mode.
ACPI: EC: lower interrupt storm treshold
ACPICA: Use spinlock for acpi_{en|dis}able_gpe
ACPI: EC: restart failed command
ACPI: EC: wait for last write gpe
ACPI: EC: make kernel messages more useful when GPE storm is detected
ACPI: EC: revert msleep patch
thinkpad_acpi: fingers off backlight if video.ko is serving this functionality
sony-laptop: fingers off backlight if video.ko is serving this functionality
msi-laptop: fingers off backlight if video.ko is serving this functionality
fujitsu-laptop: fingers off backlight if video.ko is serving this functionality
eeepc-laptop: fingers off backlight if video.ko is serving this functionality
compal: fingers off backlight if video.ko is serving this functionality
asus-acpi: fingers off backlight if video.ko is serving this functionality
Acer-WMI: fingers off backlight if video.ko is serving this functionality
ACPI video: if no ACPI backlight support, use vendor drivers
ACPI: video: Ignore devices that aren't present in hardware
Delete an unwanted return statement at evgpe.c
...
Impact: fix bootup crash
the branch tracer missed arch/x86/vdso/vclock_gettime.c from
disabling tracing, which caused such bootup crashes:
[ 201.840097] init[1]: segfault at 7fffed3fe7c0 ip 00007fffed3fea2e sp 000077
also clean up the ugly ifdefs in arch/x86/kernel/vsyscall_64.c by
creating DISABLE_UNLIKELY_PROFILE facility for code to turn off
instrumentation on a per file basis.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new unlikely/likely profiler
Andrew Morton recently suggested having an in-kernel way to profile
likely and unlikely macros. This patch achieves that goal.
When configured, every(*) likely and unlikely macro gets a counter attached
to it. When the condition is hit, the hit and misses of that condition
are recorded. These numbers can later be retrieved by:
/debugfs/tracing/profile_likely - All likely markers
/debugfs/tracing/profile_unlikely - All unlikely markers.
# cat /debug/tracing/profile_unlikely | head
correct incorrect % Function File Line
------- --------- - -------- ---- ----
2167 0 0 do_arch_prctl process_64.c 832
0 0 0 do_arch_prctl process_64.c 804
2670 0 0 IS_ERR err.h 34
71230 5693 7 __switch_to process_64.c 673
76919 0 0 __switch_to process_64.c 639
43184 33743 43 __switch_to process_64.c 624
12740 64181 83 __switch_to process_64.c 594
12740 64174 83 __switch_to process_64.c 590
# cat /debug/tracing/profile_unlikely | \
awk '{ if ($3 > 25) print $0; }' |head -20
44963 35259 43 __switch_to process_64.c 624
12762 67454 84 __switch_to process_64.c 594
12762 67447 84 __switch_to process_64.c 590
1478 595 28 syscall_get_error syscall.h 51
0 2821 100 syscall_trace_leave ptrace.c 1567
0 1 100 native_smp_prepare_cpus smpboot.c 1237
86338 265881 75 calc_delta_fair sched_fair.c 408
210410 108540 34 calc_delta_mine sched.c 1267
0 54550 100 sched_info_queued sched_stats.h 222
51899 66435 56 pick_next_task_fair sched_fair.c 1422
6 10 62 yield_task_fair sched_fair.c 982
7325 2692 26 rt_policy sched.c 144
0 1270 100 pre_schedule_rt sched_rt.c 1261
1268 48073 97 pick_next_task_rt sched_rt.c 884
0 45181 100 sched_info_dequeued sched_stats.h 177
0 15 100 sched_move_task sched.c 8700
0 15 100 sched_move_task sched.c 8690
53167 33217 38 schedule sched.c 4457
0 80208 100 sched_info_switch sched_stats.h 270
30585 49631 61 context_switch sched.c 2619
# cat /debug/tracing/profile_likely | awk '{ if ($3 > 25) print $0; }'
39900 36577 47 pick_next_task sched.c 4397
20824 15233 42 switch_mm mmu_context_64.h 18
0 7 100 __cancel_work_timer workqueue.c 560
617 66484 99 clocksource_adjust timekeeping.c 456
0 346340 100 audit_syscall_exit auditsc.c 1570
38 347350 99 audit_get_context auditsc.c 732
0 345244 100 audit_syscall_entry auditsc.c 1541
38 1017 96 audit_free auditsc.c 1446
0 1090 100 audit_alloc auditsc.c 862
2618 1090 29 audit_alloc auditsc.c 858
0 6 100 move_masked_irq migration.c 9
1 198 99 probe_sched_wakeup trace_sched_switch.c 58
2 2 50 probe_wakeup trace_sched_wakeup.c 227
0 2 100 probe_wakeup_sched_switch trace_sched_wakeup.c 144
4514 2090 31 __grab_cache_page filemap.c 2149
12882 228786 94 mapping_unevictable pagemap.h 50
4 11 73 __flush_cpu_slab slub.c 1466
627757 330451 34 slab_free slub.c 1731
2959 61245 95 dentry_lru_del_init dcache.c 153
946 1217 56 load_elf_binary binfmt_elf.c 904
102 82 44 disk_put_part genhd.h 206
1 1 50 dst_gc_task dst.c 82
0 19 100 tcp_mss_split_point tcp_output.c 1126
As you can see by the above, there's a bit of work to do in rethinking
the use of some unlikelys and likelys. Note: the unlikely case had 71 hits
that were more than 25%.
Note: After submitting my first version of this patch, Andrew Morton
showed me a version written by Daniel Walker, where I picked up
the following ideas from:
1) Using __builtin_constant_p to avoid profiling fixed values.
2) Using __FILE__ instead of instruction pointers.
3) Using the preprocessor to stop all profiling of likely
annotations from vsyscall_64.c.
Thanks to Andrew Morton, Arjan van de Ven, Theodore Tso and Ingo Molnar
for their feed back on this patch.
(*) Not ever unlikely is recorded, those that are used by vsyscalls
(a few of them) had to have profiling disabled.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
With the PMB enabled, only P1SEG and up are covered by the PMB mappings,
meaning that situations where out-of-bounds physical addresses are read
from will lead to TLB reset after the PMB miss, allowing for use cases
like dd if=/dev/mem to reset the TLB.
Fix this up to make sure the reference is between __MEMORY_START (phys)
and __pa(high_memory). This is coherent across all variants of sh/sh64
with and without MMU, though the PMB bug itself is only applicable to
SH-4A parts.
Reported-by: Hideo Saito <saito@densan.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch changes sci type of SH7723 from PORT_SCI to PORT_SCIFA.
Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This removes the acpi_irq_balance_set() interface from the PCI
interrupt link driver.
x86 used acpi_irq_balance_set() to tell the PCI interrupt link
driver to configure links to minimize IRQ sharing. But the link
driver can easily figure out whether to turn on IRQ balancing
based on the IRQ model (PIC/IOAPIC/etc), so we can get rid of
that external interface.
It's better for the driver to figure this out at init-time. If
we set it externally via the x86 code, the interface reduces
modularity, and we depend on the fact that acpi_process_madt()
happens before we process the kernel command line.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Now that the critical read back to flush the next descriptor address is
fixed we can downgrade some BUG_ONs that need only be enabled when testing
changes to the driver.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In the case of !CONFIG_SMP, raw_spinlock_t is empty and the spinlock functions
don't build. Fix by defining spinlock functions for the uniprocessor case.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
There is a potential issue that, when guest using pagetable without vmexit when
EPT enabled, guest would use PAT/PCD/PWT bits to index PAT msr for it's memory,
which would be inconsistent with host side and would cause host MCE due to
inconsistent cache attribute.
The patch set IGMT bit in EPT entry to ignore guest PAT and use WB as default
memory type to protect host (notice that all memory mapped by KVM should be WB).
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
WARNING: arch/x86/kernel/built-in.o(.text+0x1722c): Section mismatch
in reference from the function kvm_setup_secondary_clock() to the
function .devinit.text:setup_secondary_APIC_clock()
The function kvm_setup_secondary_clock() references
the function __devinit setup_secondary_APIC_clock().
This is often because kvm_setup_secondary_clock lacks a __devinit
annotation or the annotation of setup_secondary_APIC_clock is wrong.
Signed-off-by: Md.Rakib H. Mullick <rakib.mullick@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
timers: handle HRTIMER_CB_IRQSAFE_UNLOCKED correctly from softirq context
nohz: disable tick_nohz_kick_tick() for now
irq: call __irq_enter() before calling the tick_idle_check
x86: HPET: enter hpet_interrupt_handler with interrupts disabled
x86: HPET: read from HPET_Tn_CMP() not HPET_T0_CMP
x86: HPET: convert WARN_ON to WARN_ON_ONCE
Before a vcpu blocks, it should switch to the guest signal mask to allow
signals to unblock it.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
The page fault path can use two rmap_desc structures, if:
- walk_addr's dirty pte update allocates one rmap_desc.
- mmu_lock is dropped, sptes are zapped resulting in rmap_desc being
freed.
- fetch->mmu_set_spte allocates another rmap_desc.
Increase to 4 for safety.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
