Code which runs outside the kernel's normal mode of operation often does
unusual things which can cause a static analysis tool like objtool to
emit false positive warnings:
- boot image
- vdso image
- relocation
- realmode
- efi
- head
- purgatory
- modpost
Set OBJECT_FILES_NON_STANDARD for their related files and directories,
which will tell objtool to skip checking them. It's ok to skip them
because they don't affect runtime stack traces.
Also skip the following code which does the right thing with respect to
frame pointers, but is too "special" to be validated by a tool:
- entry
- mcount
Also skip the test_nx module because it modifies its exception handling
table at runtime, which objtool can't understand. Fortunately it's
just a test module so it doesn't matter much.
Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it
might eventually be useful for other tools.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull ARC fixes from Vineet Gupta:
- Fix for csd deadlock due to missing self IPI
- Accompanying IPI cleanups / optimization
- Brown paper bag bug in one of the cleanups above
- Boot reporting updates for new hardware features
- Don't force DEVTMPFS if INITRAMFS
* tag 'arc-4.5-rc6-fixes-upd' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
arc: SMP: CONFIG_ARC_IPI_DBG cleanup
ARC: SMP: No need for CONFIG_ARC_IPI_DBG
ARCv2: Elide sending new cross core intr if receiver didn't ack prev
ARCv2: SMP: Push IPI_IRQ into IPI provider
ARC: [intc-compact] Remove IPI setup from ARCompact port
ARCv2: SMP: Emulate IPI to self using software triggered interrupt
arc: get rid of DEVTMPFS dependency on INITRAMFS_SOURCE
ARCv2: boot report CCMs (Closely Coupled Memories)
ARCv2: boot print Low Latency Memory
ARC: Assume multiplier is always present
Pull vfs fixes from Al Viro:
"Assorted fixes - xattr one from this cycle, the rest - stable fodder"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs/pnode.c: treat zero mnt_group_id-s as unequal
affs_do_readpage_ofs(): just use kmap_atomic() around memcpy()
xattr handlers: plug a lock leak in simple_xattr_list
fs: allow no_seek_end_llseek to actually seek
Previous Commit ("ARC: SMP: No need for CONFIG_ARC_IPI_DBG") removed
the Kconfig option ARC_IPI_DBG. Remove the last reference on this
option.
Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
If __preempt_schedule() or __preempt_schedule_notrace() is referenced at
the beginning of a function, gcc can insert the asm inline "call
___preempt_schedule[_notrace]" instruction before setting up a stack
frame, which breaks frame pointer convention if CONFIG_FRAME_POINTER is
enabled and can result in bad stack traces.
Force a stack frame to be created if CONFIG_FRAME_POINTER is enabled by
listing the stack pointer as an output operand for the inline asm
statements.
Specifically this fixes the following stacktool warnings:
stacktool: drivers/scsi/hpsa.o: hpsa_scsi_do_simple_cmd.constprop.106()+0x79: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x70: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_find_first()+0x92: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_free()+0xff: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_free()+0xf5: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_free()+0x11a: call without frame pointer save/setup
stacktool: fs/mbcache.o: mb_cache_entry_get()+0x225: call without frame pointer save/setup
stacktool: kernel/locking/percpu-rwsem.o: percpu_up_read()+0x27: call without frame pointer save/setup
stacktool: kernel/profile.o: do_profile_hits.isra.5()+0x139: call without frame pointer save/setup
stacktool: lib/nmi_backtrace.o: nmi_trigger_all_cpu_backtrace()+0x2b6: call without frame pointer save/setup
stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_recv()+0x58: call without frame pointer save/setup
stacktool: net/rds/ib_cm.o: rds_ib_cq_comp_handler_send()+0x58: call without frame pointer save/setup
stacktool: net/rds/ib_recv.o: rds_ib_attempt_ack()+0xc1: call without frame pointer save/setup
stacktool: net/rds/iw_recv.o: rds_iw_attempt_ack()+0xc1: call without frame pointer save/setup
stacktool: net/rds/iw_recv.o: rds_iw_recv_cq_comp_handler()+0x55: call without frame pointer save/setup
So it only adds a stack frame to 15 call sites out of ~5000 calls to
___preempt_schedule[_notrace](). All the others already had stack frames.
Oddly, this change actually seems to make things faster in a lot of
cases. For many smaller functions it causes the stack frame creation to
get moved out of the common path and into the unlikely path.
For example, here's the original cyc2ns_read_end():
ffffffff8101f8c0 <cyc2ns_read_end>:
ffffffff8101f8c0: 55 push %rbp
ffffffff8101f8c1: 48 89 e5 mov %rsp,%rbp
ffffffff8101f8c4: 83 6f 10 01 subl $0x1,0x10(%rdi)
ffffffff8101f8c8: 75 08 jne ffffffff8101f8d2 <cyc2ns_read_end+0x12>
ffffffff8101f8ca: 65 48 89 3d e6 5a ff mov %rdi,%gs:0x7eff5ae6(%rip) # 153b8 <cyc2ns+0x38>
ffffffff8101f8d1: 7e
ffffffff8101f8d2: 65 ff 0d 77 c4 fe 7e decl %gs:0x7efec477(%rip) # bd50 <__preempt_count>
ffffffff8101f8d9: 74 02 je ffffffff8101f8dd <cyc2ns_read_end+0x1d>
ffffffff8101f8db: 5d pop %rbp
ffffffff8101f8dc: c3 retq
ffffffff8101f8dd: e8 1e 37 fe ff callq ffffffff81003000 <___preempt_schedule>
ffffffff8101f8e2: 5d pop %rbp
ffffffff8101f8e3: c3 retq
ffffffff8101f8e4: 66 66 66 2e 0f 1f 84 data16 data16 nopw %cs:0x0(%rax,%rax,1)
ffffffff8101f8eb: 00 00 00 00 00
And here's the same function with the patch:
ffffffff8101f8c0 <cyc2ns_read_end>:
ffffffff8101f8c0: 83 6f 10 01 subl $0x1,0x10(%rdi)
ffffffff8101f8c4: 75 08 jne ffffffff8101f8ce <cyc2ns_read_end+0xe>
ffffffff8101f8c6: 65 48 89 3d ea 5a ff mov %rdi,%gs:0x7eff5aea(%rip) # 153b8 <cyc2ns+0x38>
ffffffff8101f8cd: 7e
ffffffff8101f8ce: 65 ff 0d 7b c4 fe 7e decl %gs:0x7efec47b(%rip) # bd50 <__preempt_count>
ffffffff8101f8d5: 74 01 je ffffffff8101f8d8 <cyc2ns_read_end+0x18>
ffffffff8101f8d7: c3 retq
ffffffff8101f8d8: 55 push %rbp
ffffffff8101f8d9: 48 89 e5 mov %rsp,%rbp
ffffffff8101f8dc: e8 1f 37 fe ff callq ffffffff81003000 <___preempt_schedule>
ffffffff8101f8e1: 5d pop %rbp
ffffffff8101f8e2: c3 retq
ffffffff8101f8e3: 66 66 66 66 2e 0f 1f data16 data16 data16 nopw %cs:0x0(%rax,%rax,1)
ffffffff8101f8ea: 84 00 00 00 00 00
Notice that it moved the frame pointer setup code to the unlikely
___preempt_schedule() call path. Going through a sampling of the
differences in the asm, that's the most common change I see.
Otherwise it has no real effect on callers which already have stack
frames (though it does result in the reordering of some 'mov's).
Reported-by: Jiri Slaby <jslaby@suse.cz>
Tested-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20160218174158.GA28230@treble.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ARConnect/MCIP IPI sending has a retry-wait loop in case caller had
not seen a previous such interrupt. Turns out that it is not needed at
all. Linux cross core calling allows coalescing multiple IPIs to same
receiver - it is fine as long as there is one.
This logic is built into upper layer already, at a higher level of
abstraction. ipi_send_msg_one() sets the actual msg payload, but it only
calls MCIP IPI sending if msg holder was empty (using
atomic-set-new-and-get-old construct). Thus it is unlikely that the
retry-wait looping was ever getting exercised at all.
Cc: Chuck Jordan <cjordan@synopsys.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
There is no real ARC700 based SMP SoC so remove IPI definition.
EZChip's SMP ARC700 is going to use a different intc and IPI provider
anyways.
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARConnect/MCIP Inter-Core-Interrupt module can't send interrupt to
local core. So use core intc capability to trigger software
interrupt to self, using an unsued IRQ #21.
This showed up as csd deadlock with LTP trace_sched on a dual core
system. This test acts as scheduler fuzzer, triggering all sorts of
schedulting activity. Trouble starts with IPI to self, which doesn't get
delivered (effectively lost due to H/w capability), but the msg intended
to be sent remain enqueued in per-cpu @ipi_data.
All subsequent IPIs to this core from other cores get elided due to the
IPI coalescing optimization in ipi_send_msg_one() where a pending msg
implies an IPI already sent and assumes other core is yet to ack it.
After the elided IPI, other core simply goes into csd_lock_wait()
but never comes out as this core never sees the interrupt.
Fixes STAR 9001008624
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org> [4.2]
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Pull device mapper fix from Mike Snitzer:
"Fix a 112 byte leak for each IO request that is requeued while DM
multipath is handling faults due to path failures.
This leak does not happen if blk-mq DM multipath is used. It only
occurs if .request_fn DM multipath is stacked ontop of blk-mq paths
(e.g. scsi-mq devices)"
* tag 'dm-4.5-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm: fix dm_rq_target_io leak on faults with .request_fn DM w/ blk-mq paths
Pull MMC fix from Ulf Hansson:
"Here's an mmc fix intended for v4.5 rc6.
MMC host:
- omap_hsmmc: Fix PM regression for deferred probe"
* tag 'mmc-v4.5-rc4' of git://git.linaro.org/people/ulf.hansson/mmc:
mmc: omap_hsmmc: Fix PM regression with deferred probe for pm_runtime_reinit
Pull NFS client bugfixes from Trond Myklebust:
"Stable bugfixes:
- Fix nfs_size_to_loff_t
- NFSv4: Fix a dentry leak on alias use
Other bugfixes:
- Don't schedule a layoutreturn if the layout segment can be freed
immediately.
- Always set NFS_LAYOUT_RETURN_REQUESTED with lo->plh_return_iomode
- rpcrdma_bc_receive_call() should init rq_private_buf.len
- fix stateid handling for the NFS v4.2 operations
- pnfs/blocklayout: fix a memeory leak when using,vmalloc_to_page
- fix panic in gss_pipe_downcall() in fips mode
- Fix a race between layoutget and pnfs_destroy_layout
- Fix a race between layoutget and bulk recalls"
* tag 'nfs-for-4.5-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4.x/pnfs: Fix a race between layoutget and bulk recalls
NFSv4.x/pnfs: Fix a race between layoutget and pnfs_destroy_layout
auth_gss: fix panic in gss_pipe_downcall() in fips mode
pnfs/blocklayout: fix a memeory leak when using,vmalloc_to_page
nfs4: fix stateid handling for the NFS v4.2 operations
NFSv4: Fix a dentry leak on alias use
xprtrdma: rpcrdma_bc_receive_call() should init rq_private_buf.len
pNFS: Always set NFS_LAYOUT_RETURN_REQUESTED with lo->plh_return_iomode
pNFS: Fix pnfs_mark_matching_lsegs_return()
nfs: fix nfs_size_to_loff_t
In commit 11f1a4b975 ("x86: reorganize SMAP handling in user space
accesses") I changed how the stac/clac instructions were generated
around the user space accesses, which then made it possible to do
batched accesses efficiently for user string copies etc.
However, in doing so, I completely spaced out, and didn't even think
about the 32-bit case. And nobody really even seemed to notice, because
SMAP doesn't even exist until modern Skylake processors, and you'd have
to be crazy to run 32-bit kernels on a modern CPU.
Which brings us to Andy Lutomirski.
He actually tested the 32-bit kernel on new hardware, and noticed that
it doesn't work. My bad. The trivial fix is to add the required
uaccess begin/end markers around the raw accesses in <asm/uaccess_32.h>.
I feel a bit bad about this patch, just because that header file really
should be cleaned up to avoid all the duplicated code in it, and this
commit just expands on the problem. But this just fixes the bug without
any bigger cleanup surgery.
Reported-and-tested-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Even though DEVTMPFS is required when our pre-built initramfs
is used it is not the case in general. It is perfectly possible
to use initramfs with device nodes already populated or there
could be other usages, see discussion below for more detials:
http://thread.gmane.org/gmane.comp.embedded.openwrt.devel/37819/focus=37821
This change removes mentioned dependency from arch/arc/Kconfig
updating instead those defconfigs that are usually used with this
kind of pre-build initramfs.
And while at it all touched defconfigs were regenerated via
savedefconfig and some options were removed:
* USB is selected by other options implicitly
* VGA_CONSOLE is disableb for ARC since
031e29b587
* EXT3_FS automatically selects EXT4_FS
* MTDxxx and JFFS2_FS make no sense for AXS because
AXS NAND controller is not upstreamed
* NET_OSCI_LAN is not in upstream as well
* ARCPGU_xxx options make no sense because ARC PGU is not yet
in upstream and when it gets there all config options would
be taken from devicetree
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Replace another case where the layout 'plh_block_lgets' can trigger
infinite loops in send_layoutget().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the server reboots while there is a layoutget outstanding, then
the call to pnfs_choose_layoutget_stateid() will fail with an EAGAIN
error, which causes an infinite loop in send_layoutget(). The reason
why we never break out of the loop is that the layout 'plh_block_lgets'
field is never cleared.
Fix is to replace plh_block_lgets with NFS_LAYOUT_INVALID_STID, which
can be reset after a new layoutget.
Fixes: ab7d763e47 ("pNFS: Ensure nfs4_layoutget_prepare returns...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull tracing fixes from Steven Rostedt:
"Two more small fixes.
One is by Yang Shi who added a READ_ONCE_NOCHECK() to the scan of the
stack made by the stack tracer. As the stack tracer scans the entire
kernel stack, KASAN triggers seeing it as a "stack out of bounds"
error. As the scan is looking at the contents of the stack from
parent functions. The NOCHECK() tells KASAN that this is done on
purpose, and is not some kind of stack overflow.
The second fix is to the ftrace selftests, to retrieve the PID of
executed commands from the shell with '$!' and not by parsing 'jobs'"
* tag 'trace-fixes-v4.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing, kasan: Silence Kasan warning in check_stack of stack_tracer
ftracetest: Fix instance test to use proper shell command for pids
Pull xen bug fixes from David Vrabel:
- Two scsiback fixes (resource leak and spurious warning).
- Fix DMA mapping of compound pages on arm/arm64.
- Fix some pciback regressions in MSI-X handling.
- Fix a pcifront crash due to some uninitialize state.
* tag 'for-linus-4.5-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen/pcifront: Fix mysterious crashes when NUMA locality information was extracted.
xen/pcifront: Report the errors better.
xen/pciback: Save the number of MSI-X entries to be copied later.
xen/pciback: Check PF instead of VF for PCI_COMMAND_MEMORY
xen: fix potential integer overflow in queue_reply
xen/arm: correctly handle DMA mapping of compound pages
xen/scsiback: avoid warnings when adding multiple LUNs to a domain
xen/scsiback: correct frontend counting
Pull networking fixes from David Miller:
"Looks like a lot, but mostly driver fixes scattered all over as usual.
Of note:
1) Add conditional sched in nf conntrack in cleanup to avoid NMI
watchdogs. From Florian Westphal.
2) Fix deadlock in nfnetlink cttimeout, also from Floarian.
3) Fix handling of slaves in bonding ARP monitor validation, from Jay
Vosburgh.
4) Callers of ip_cmsg_send() are responsible for freeing IP options,
some were not doing so. Fix from Eric Dumazet.
5) Fix per-cpu bugs in mvneta driver, from Gregory CLEMENT.
6) Fix vlan handling in mv88e6xxx DSA driver, from Vivien Didelot.
7) bcm7xxx PHY driver bug fixes from Florian Fainelli.
8) Avoid unaligned accesses to protocol headers wrt. GRE, from
Alexander Duyck.
9) SKB leaks and other problems in arc_emac driver, from Alexander
Kochetkov.
10) tcp_v4_inbound_md5_hash() releases listener socket instead of
request socket on error path, oops. Fix from Eric Dumazet.
11) Missing socket release in pppoe_rcv_core() that seems to have
existed basically forever. From Guillaume Nault.
12) Missing slave_dev unregister in dsa_slave_create() error path,
from Florian Fainelli.
13) crypto_alloc_hash() never returns NULL, fix return value check in
__tcp_alloc_md5sig_pool. From Insu Yun.
14) Properly expire exception route entries in ipv4, from Xin Long.
15) Fix races in tcp/dccp listener socket dismantle, from Eric
Dumazet.
16) Don't set IFF_TX_SKB_SHARING in vxlan, geneve, or GRE, it's not
legal. These drivers modify the SKB on transmit. From Jiri Benc.
17) Fix regression in the initialziation of netdev->tx_queue_len.
From Phil Sutter.
18) Missing unlock in tipc_nl_add_bc_link() error path, from Insu Yun.
19) SCTP port hash sizing does not properly ensure that table is a
power of two in size. From Neil Horman.
20) Fix initializing of software copy of MAC address in fmvj18x_cs
driver, from Ken Kawasaki"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (129 commits)
bnx2x: Fix 84833 phy command handler
bnx2x: Fix led setting for 84858 phy.
bnx2x: Correct 84858 PHY fw version
bnx2x: Fix 84833 RX CRC
bnx2x: Fix link-forcing for KR2
net: ethernet: davicom: fix devicetree irq resource
fmvj18x_cs: fix incorrect indexing of dev->dev_addr[] when copying the MAC address
Driver: Vmxnet3: Update Rx ring 2 max size
net: netcp: rework the code for get/set sw_data in dma desc
soc: ti: knav_dma: rename pad in struct knav_dma_desc to sw_data
net: ti: netcp: restore get/set_pad_info() functionality
MAINTAINERS: Drop myself as xen netback maintainer
sctp: Fix port hash table size computation
can: ems_usb: Fix possible tx overflow
Bluetooth: hci_core: Avoid mixing up req_complete and req_complete_skb
net: bcmgenet: Fix internal PHY link state
af_unix: Don't use continue to re-execute unix_stream_read_generic loop
unix_diag: fix incorrect sign extension in unix_lookup_by_ino
bnxt_en: Failure to update PHY is not fatal condition.
bnxt_en: Remove unnecessary call to update PHY settings.
...
Pull hwmon fixes from Guenter Roeck:
"Two fixes headed for stable:
- Remove an unnecessary speed_index lookup for thermal hook in the
gpio-fan driver. The unnecessary speed lookup can hog the system.
- Handle negative conversion values correctly in the ads1015 driver"
* tag 'hwmon-for-linus-v4.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: (gpio-fan) Remove un-necessary speed_index lookup for thermal hook
hwmon: (ads1015) Handle negative conversion values correctly
