Age | Commit message (Collapse) | Author |
|
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (31 commits)
ftrace: fix current_tracer error return
tracing: fix a build error on alpha
ftrace: use a real variable for ftrace_nop in x86
tracing/ftrace: make boot tracer select the sched_switch tracer
tracepoint: check if the probe has been registered
asm-generic: define DIE_OOPS in asm-generic
trace: fix printk warning for u64
ftrace: warning in kernel/trace/ftrace.c
ftrace: fix build failure
ftrace, powerpc, sparc64, x86: remove notrace from arch ftrace file
ftrace: remove ftrace hash
ftrace: remove mcount set
ftrace: remove daemon
ftrace: disable dynamic ftrace for all archs that use daemon
ftrace: add ftrace warn on to disable ftrace
ftrace: only have ftrace_kill atomic
ftrace: use probe_kernel
ftrace: comment arch ftrace code
ftrace: return error on failed modified text.
ftrace: dynamic ftrace process only text section
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm
* 'kvm-updates/2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: ia64: Makefile fix for forcing to re-generate asm-offsets.h
KVM: Future-proof device assignment ABI
KVM: ia64: Fix halt emulation logic
KVM: Fix guest shared interrupt with in-kernel irqchip
KVM: MMU: sync root on paravirt TLB flush
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
lockdep: fix irqs on/off ip tracing
lockdep: minor fix for debug_show_all_locks()
x86: restore the old swiotlb alloc_coherent behavior
x86: use GFP_DMA for 24bit coherent_dma_mask
swiotlb: remove panic for alloc_coherent failure
xen: compilation fix of drivers/xen/events.c on IA64
xen: portability clean up and some minor clean up for xencomm.c
xen: don't reload cr3 on suspend
kernel/resource: fix reserve_region_with_split() section mismatch
printk: remove unused code from kernel/printk.c
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, memory hotplug: remove wrong -1 in calling init_memory_mapping()
x86: keep the /proc/meminfo page count correct
x86/uv: memory allocation at initialization
xen: fix Xen domU boot with batched mprotect
|
|
To avoid using stale asm-offsets.h.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
|
|
Common halt logic was changed by x86 and did not update ia64. This patch
updates halt for ia64.
Fixes a regression causing guests to hang with more than 2 vcpus.
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
|
|
Every call of kvm_set_irq() should offer an irq_source_id, which is
allocated by kvm_request_irq_source_id(). Based on irq_source_id, we
identify the irq source and implement logical OR for shared level
interrupts.
The allocated irq_source_id can be freed by kvm_free_irq_source_id().
Currently, we support at most sizeof(unsigned long) different irq sources.
[Amit: - rebase to kvm.git HEAD
- move definition of KVM_USERSPACE_IRQ_SOURCE_ID to common file
- move kvm_request_irq_source_id to the update_irq ioctl]
[Xiantao: - Add kvm/ia64 stuff and make it work for kvm/ia64 guests]
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
|
|
The pvmmu TLB flush handler should request a root sync, similarly to
a native read-write CR3.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
|
|
The s390 kernel does not compile if virtio console is enabled, but guest
support is disabled:
LD .tmp_vmlinux1
arch/s390/kernel/built-in.o: In function `setup_arch':
/space/linux-2.5/arch/s390/kernel/setup.c:773: undefined reference to
`s390_virtio_console_init'
The fix is related to
commit 99e65c92f2bbf84f43766a8bf701e36817d62822
Author: Christian Borntraeger <borntraeger@de.ibm.com>
Date: Fri Jul 25 15:50:04 2008 +0200
KVM: s390: Fix guest kconfig
Which changed the build process to build kvm_virtio.c only if CONFIG_S390_GUEST
is set. We must ifdef the prototype in the header file accordingly.
Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
We got a stack overflow with a small stack configuration on a 32 bit
system. It just looks like as 4kb isn't enough and too dangerous.
So lets get rid of 4kb stacks on 32 bit.
But one thing I completely dislike about the call trace below is that
just for debugging or tracing purposes sprintf gets called (cio_start_key):
/* process condition code */
sprintf(dbf_txt, "ccode:%d", ccode);
CIO_TRACE_EVENT(4, dbf_txt);
But maybe its just me who thinks that this could be done better.
<4>Kernel stack overflow.
<4>Modules linked in: dm_multipath sunrpc bonding qeth_l2 dm_mod qeth ccwgroup vmur
<4>CPU: 1 Not tainted 2.6.27-30.x.20081015-s390default #1
<4>Process httpd (pid: 3807, task: 20ae2df8, ksp: 1666fb78)
<4>Krnl PSW : 040c0000 8027098a (number+0xe/0x348)
<4> R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:0 PM:0
<4>Krnl GPRS: 00d43318 0027097c 1666f277 9666f270
<4> 00000000 00000000 0000000a ffffffff
<4> 9666f270 1666f228 1666f277 1666f098
<4> 00000002 80270982 80271016 1666f098
<4>Krnl Code: 8027097e: f0340dd0a7f1 srp 3536(4,%r0),2033(%r10),4
<4> 80270984: 0f00 clcl %r0,%r0
<4> 80270986: a7840001 brc 8,80270988
<4> >8027098a: 18ef lr %r14,%r15
<4> 8027098c: a7faff68 ahi %r15,-152
<4> 80270990: 18bf lr %r11,%r15
<4> 80270992: 18a2 lr %r10,%r2
<4> 80270994: 1893 lr %r9,%r3
Modified calltrace with annotated stackframe size of each function:
stackframe size
|
0 304 vsnprintf+850 [0x271016]
1 72 sprintf+74 [0x271522]
2 56 cio_start_key+262 [0x2d4c16]
3 56 ccw_device_start_key+222 [0x2dfe92]
4 56 ccw_device_start+40 [0x2dff28]
5 48 raw3215_start_io+104 [0x30b0f8]
6 56 raw3215_write+494 [0x30ba0a]
7 40 con3215_write+68 [0x30bafc]
8 40 __call_console_drivers+146 [0x12b0fa]
9 32 _call_console_drivers+102 [0x12b192]
10 64 release_console_sem+268 [0x12b614]
11 168 vprintk+462 [0x12bca6]
12 72 printk+68 [0x12bfd0]
13 256 __print_symbol+50 [0x15a882]
14 56 __show_trace+162 [0x103d06]
15 32 show_trace+224 [0x103e70]
16 48 show_stack+152 [0x103f20]
17 56 dump_stack+126 [0x104612]
18 96 __alloc_pages_internal+592 [0x175004]
19 80 cache_alloc_refill+776 [0x196f3c]
20 40 __kmalloc+258 [0x1972ae]
21 40 __alloc_skb+94 [0x328086]
22 32 pskb_copy+50 [0x328252]
23 32 skb_realloc_headroom+110 [0x328a72]
24 104 qeth_l2_hard_start_xmit+378 [0x7803bfde]
25 56 dev_hard_start_xmit+450 [0x32ef6e]
26 56 __qdisc_run+390 [0x3425d6]
27 48 dev_queue_xmit+410 [0x331e06]
28 40 ip_finish_output+308 [0x354ac8]
29 56 ip_output+218 [0x355b6e]
30 24 ip_local_out+56 [0x354584]
31 120 ip_queue_xmit+300 [0x355cec]
32 96 tcp_transmit_skb+812 [0x367da8]
33 40 tcp_push_one+158 [0x369fda]
34 112 tcp_sendmsg+852 [0x35d5a0]
35 240 sock_sendmsg+164 [0x32035c]
36 56 kernel_sendmsg+86 [0x32064a]
37 88 sock_no_sendpage+98 [0x322b22]
38 104 tcp_sendpage+70 [0x35cc1e]
39 48 sock_sendpage+74 [0x31eb66]
40 64 pipe_to_sendpage+102 [0x1c4b2e]
41 64 __splice_from_pipe+120 [0x1c5340]
42 72 splice_from_pipe+90 [0x1c57e6]
43 56 generic_splice_sendpage+38 [0x1c5832]
44 48 do_splice_from+104 [0x1c4c38]
45 48 direct_splice_actor+52 [0x1c4c88]
46 80 splice_direct_to_actor+180 [0x1c4f80]
47 72 do_splice_direct+70 [0x1c5112]
48 64 do_sendfile+360 [0x19de18]
49 72 sys_sendfile64+126 [0x19df32]
50 336 sysc_do_restart+18 [0x111a1a]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
allyesconfig and allmodconfig built kernels have a tape IPL record.
A the vmreader record makes much more sense, since hardly anybody will
ever IPL a kernel from tape. So change the default.
As I side effect I can test these kernels without fiddling around with
the kernel config ;)
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
unsigned ops->size cannot be negative
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
Use sysdev_class_create_file() to create create sysdev class attributes
instead of sysfs_create_file(). Using sysfs_create_file() wasn't a very
good idea since the show and store functions have a different amount of
parameters for sysfs files and sysdev class files.
In particular the pointer to the buffer is the last argument and
therefore accesses to random memory regions happened.
Still worked surprisingly well until we got a kernel panic.
Cc: stable@kernel.org
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
The current enable_sie code sets the mm->context.pgstes bit to tell
dup_mm that the new mm should have extended page tables. This bit is also
used by the s390 specific page table primitives to decide about the page
table layout - which means context.pgstes has two meanings. This can cause
any kind of bugs. For example - e.g. shrink_zone can call
ptep_clear_flush_young while enable_sie is running. ptep_clear_flush_young
will test for context.pgstes. Since enable_sie changed that value of the old
struct mm without changing the page table layout ptep_clear_flush_young will
do the wrong thing.
The solution is to split pgstes into two bits
- one for the allocation
- one for the current state
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
|
Impact: fix crash with memory hotplug
Shuahua Li found:
| I just did some experiments on a desktop for memory hotplug and this bug
| triggered a crash in my test.
|
| Yinghai's suggestion also fixed the bug.
We don't need to round it, just remove that extra -1
Signed-off-by: Yinghai <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Impact: get correct page count in /proc/meminfo
found page count in /proc/meminfo is nor correct on 1G system in VirtualBox 2.0.4
# cat /proc/meminfo
MemTotal: 1017508 kB
MemFree: 822700 kB
Buffers: 1456 kB
Cached: 26632 kB
SwapCached: 0 kB
...
Hugepagesize: 2048 kB
DirectMap4k: 4032 kB
DirectMap2M: 18446744073709549568 kB
with this patch get:
...
DirectMap4k: 4032 kB
DirectMap2M: 1044480 kB
which is consistent to kernel_page_tables
---[ Low Kernel Mapping ]---
0xffff880000000000-0xffff880000001000 4K RW PCD GLB x pte
0xffff880000001000-0xffff88000009f000 632K RW GLB x pte
0xffff88000009f000-0xffff8800000a0000 4K RW PCD GLB x pte
0xffff8800000a0000-0xffff880000200000 1408K RW GLB x pte
0xffff880000200000-0xffff88003fe00000 1020M RW PSE GLB x pmd
0xffff88003fe00000-0xffff88003fff0000 1984K RW GLB NX pte
0xffff88003fff0000-0xffff880040000000 64K pte
0xffff880040000000-0xffff888000000000 511G pud
0xffff888000000000-0xffffc20000000000 58880G pgd
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
|
Signed-off-by: Zhang Le <r0bertz@gentoo.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
When booting Linux on a txx9 board with VxWorks boot loader, it crashes in
prom_getenv(), as VxWorks doesn't pass firmware parameters in a0-a3 (in my
case, the actual leftover values in these registers were 0x80002000,
0x80001fe0, 0x2000, and 0x20).
Make the parsing of argc, argv, and envp a bit more robust by checking if
argc is a number below CKSEG0, and argv/envp point to CKSEG0.
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
These functions are completely ineffective.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Remove runtime db_* macros as we don't need them any more. In general,
such helpers are useful for initial porting, but once approved, they are
not indispensable.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Current EMMA2RH irq code is mess. Before cleaning it up, gather them
in one place as a first step.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Let's use immediate value, instead. This also saves memory footprint,
and probably a little bit faster.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Let's use immediate value, instead. This also saves memory footprint,
and probably a little bit faster.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Let's use immediate value, instead. This also saves memory footprint,
and probably a little bit faster.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
It's totally a waste of CPU cycles.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
We'll put all EMMA related headers there in the future.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
git mv arch/mips/{emma2rh,emma} and fixups Makefiles. We'll put all NEC
EMMA series based machines there in the future.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
- Move EMMA related stuff into arch/mips/emma/Kconfig
- Create CONFIG_SOC_EMMA* to handle more EMMA SoCs effectively
- Rename CONFIG_MARKEINS into CONFIG_NEC_MARKEINS
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
We already have sufficient infrastructure to support VR5500 and VR5500A
series processors. Here's a Makefile support to make it selectable by
ports, and enable it for NEC EMMA2RH Markeins board.
This patch also fixes a confused target help, and adds 1Gb PageMask bits
supported by VR5500 and its variants.
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
The following patch add support for the NXP PNX833x SOC. More
specifically it adds support for the STB222/5 variant. It fixes
the vectored interrupt issue.
Signed-off-by: daniel.j.laird <daniel.j.laird@nxp.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Fix a typo in the comment for the TOSHIBA_RBTX4939 config option
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
In file included from include/linux/ptrace.h:49,
from arch/mips/kernel/kgdb.c:25:
/home/yuasa/src/linux/test/mips/linux/arch/mips/include/asm/ptrace.h:123: error: expected declaration specifiers or '...' before '__s64'
/home/yuasa/src/linux/test/mips/linux/arch/mips/include/asm/ptrace.h:124: error: expected declaration specifiers or '...' before '__s64'
/home/yuasa/src/linux/test/mips/linux/arch/mips/include/asm/ptrace.h:126: error: expected declaration specifiers or '...' before '__u32'
/home/yuasa/src/linux/test/mips/linux/arch/mips/include/asm/ptrace.h:127: error: expected declaration specifiers or '...' before '__u32'
make[1]: *** [arch/mips/kernel/kgdb.o] Error 1
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
The following functions
disable_local1_irq()
disable_local2_irq()
disable_local3_irq()
are needlessly defined global, so make them static. While at it, fix a
whitespace error in the same file.
Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.fi>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Add smc91x platform device to RBTX4939 board and some hacks for big endian.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Add sysfs interface for 7 segment LED and implement access routine for
RBTX4939.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Add au1xmmc platform data for PB1200/DB1200 boards and wire up the 2 SD
controllers for them.
Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
This patch sets the correct interrupt status and level
in order to get the CompactFlash adapter working.
Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
mips/pci/fixup-rc32434.c must #include <asm/mach-rc32434/irq.h>
This patch fixes the following compile error caused by
commit 606a083b1e1a357cb66454e4581b80f1a67d8368
(MIPS: RB532: Cleanup the headers again):
<-- snip -->
...
CC arch/mips/pci/fixup-rc32434.o
arch/mips/pci/fixup-rc32434.c: In function 'pcibios_map_irq':
arch/mips/pci/fixup-rc32434.c:46: error: 'GROUP4_IRQ_BASE' undeclared (first use in this function)
arch/mips/pci/fixup-rc32434.c:46: error: (Each undeclared identifier is reported only once
arch/mips/pci/fixup-rc32434.c:46: error: for each function it appears in.)
make[2]: *** [arch/mips/pci/fixup-rc32434.o] Error 1
<-- snip -->
A virtually identical patch was also submitted by Yoichi Yuasa
<yoichi_yuasa@tripeaks.co.jp>.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
<asm/ptrace.h> is exported to userland so can't include <linux/ptrace.h>,
so replace the C99 types with their basic C type equivalents.
Bug originally reported and initial patch by Yoichi Yuasa
<yoichi_yuasa@tripeaks.co.jp>.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Noticed by Anirban Sinha <ASinha@zeugmasystems.com>; patch by me.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
We were getting away with this for so long only because the only platform
with a non-empty plat_unmap_dma_mem() doesn't call dma_sync_sg_for_cpu()
and dma_sync_sg_for_device() from its commonly used drivers.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
debugfs_create_*() returns NULL on error. Make its callers return -ENODEV
on error.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
debugfs_create_*() returns NULL on error. Make its caller debugfs_fpuemu
return -ENODEV on error.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
|
|
Impact: avoid section mismatch warning, clean up
The dynamic ftrace determines which nop is safe to use at start up.
When it finds a safe nop for patching, it sets a pointer called ftrace_nop
to point to the code. All call sites are then patched to this nop.
Later, when tracing is turned on, this ftrace_nop variable is again used
to compare the location to make sure it is a nop before we update it to
an mcount call. If this fails just once, a warning is printed and ftrace
is disabled.
Rakib Mullick noted that the code that sets up the nop is a .init section
where as the nop itself is in the .text section. This is needed because
the nop is used later on after boot up. The problem is that the test of the
nop jumps back to the setup code and causes a "section mismatch" warning.
Rakib first recommended to convert the nop to .init.text, but as stated
above, this would fail since that text is used later.
The real solution is to extend Rabik's patch, and to make the ftrace_nop
into an array, and just save the code from the assembly to this array.
Now the section can stay as an init section, and we have a nop to use
later on.
Reported-by: Rakib Mullick <rakib.mullick@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
|