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Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.
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Pull perf fixes from Ingo Molnar:
"Two fixlets"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/hwbp: Simplify the perf-hwbp code, fix documentation
perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUs
Pull x86 fixes from Ingo Molnar:
"Two UV platform fixes, and a kbuild fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform/UV: Fix critical UV MMR address error
x86/platform/uv/BAU: Add APIC idt entry
x86/purgatory: Avoid creating stray .<pid>.d files, remove -MD from KBUILD_CFLAGS
Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the
modification of a breakpoint - simplify it and remove the pointless
local variables.
Also update the stale Docbook while at it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 PTI fixes from Ingo Molnar:
"Two fixes: a relatively simple objtool fix that makes Clang built
kernels work with ORC debug info, plus an alternatives macro fix"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/alternatives: Fixup alternative_call_2
objtool: Add Clang support
A critical error was found testing the fixed UV4 HUB in that an MMR address
was found to be incorrect. This causes the virtual address space for
accessing the MMIOH1 region to be allocated with the incorrect size.
Fixes: 673aa20c55a1 ("x86/platform/UV: Update uv_mmrs.h to prepare for UV4A fixes")
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: Russ Anderson <russ.anderson@hpe.com>
Cc: Andrew Banman <andrew.banman@hpe.com>
Link: https://lkml.kernel.org/r/20180328174011.041801248@stormcage.americas.sgi.com
this patch fix a bug in how the pebs->real_ip is handled in the PEBS
handler. real_ip only exists in Haswell and later processor. It is
actually the eventing IP, i.e., where the event occurred. As opposed
to the pebs->ip which is the PEBS interrupt IP which is always off
by one.
The problem is that the real_ip just like the IP needs to be fixed up
because PEBS does not record all the machine state registers, and
in particular the code segement (cs). This is why we have the set_linear_ip()
function. The problem was that set_linear_ip() was only used on the pebs->ip
and not the pebs->real_ip.
We have profiles which ran into invalid callstacks because of this.
Here is an example:
..... 0: ffffffffffffff80 recent entry, marker kernel v
..... 1: 000000000040044d <= user address in kernel space!
..... 2: fffffffffffffe00 marker enter user v
..... 3: 000000000040044d
..... 4: 00000000004004b6 oldest entry
Debugging output in get_perf_callchain():
[ 857.769909] CALLCHAIN: CPU8 ip=40044d regs->cs=10 user_mode(regs)=0
The problem is that the kernel entry in 1: points to a user level
address. How can that be?
The reason is that with PEBS sampling the instruction that caused the event
to occur and the instruction where the CPU was when the interrupt was posted
may be far apart. And sometime during that time window, the privilege level may
change. This happens, for instance, when the PEBS sample is taken close to a
kernel entry point. Here PEBS, eventing IP (real_ip) captured a user level
instruction. But by the time the PMU interrupt fired, the processor had already
entered kernel space. This is why the debug output shows a user address with
user_mode() false.
The problem comes from PEBS not recording the code segment (cs) register.
The register is used in x86_64 to determine if executing in kernel vs user
space. This is okay because the kernel has a software workaround called
set_linear_ip(). But the issue in setup_pebs_sample_data() is that
set_linear_ip() is never called on the real_ip value when it is available
(Haswell and later) and precise_ip > 1.
This patch fixes this problem and eliminates the callchain discrepancy.
The patch restructures the code around set_linear_ip() to minimize the number
of times the IP has to be set.
Signed-off-by: Stephane Eranian <eranian@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: kan.liang@intel.com
Link: http://lkml.kernel.org/r/1521788507-10231-1-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull Kbuild fixes from Masahiro Yamada:
- fix missed rebuild of TRIM_UNUSED_KSYMS
- fix rpm-pkg for GNU tar >= 1.29
- include scripts/dtc/include-prefixes/* to kernel header deb-pkg
- add -no-integrated-as option ealier to fix building with Clang
- fix netfilter Makefile for parallel building
* tag 'kbuild-fixes-v4.16-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
netfilter: nf_nat_snmp_basic: add correct dependency to Makefile
kbuild: rpm-pkg: Support GNU tar >= 1.29
builddeb: Fix header package regarding dtc source links
kbuild: set no-integrated-as before incl. arch Makefile
kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
The following pattern fails to compile while the same pattern
with alternative_call() does:
if (...)
alternative_call_2(...);
else
alternative_call_2(...);
as it expands into
if (...)
{
}; <===
else
{
};
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20180114120504.GA11368@avx2
BAU uses the old alloc_initr_gate90 method to setup its interrupt. This
fails silently as the BAU vector is in the range of APIC vectors that are
registered to the spurious interrupt handler. As a consequence BAU
broadcasts are not handled, and the broadcast source CPU hangs.
Update BAU to use new idt structure.
Fixes: dc20b2d52653 ("x86/idt: Move interrupt gate initialization to IDT code")
Signed-off-by: Andrew Banman <abanman@hpe.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mike Travis <mike.travis@hpe.com>
Cc: Dimitri Sivanich <sivanich@hpe.com>
Cc: Russ Anderson <rja@hpe.com>
Cc: stable@vger.kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/1522188546-196177-1-git-send-email-abanman@hpe.com
Pull networking fixes from David Miller:
1) Fix RCU locking in xfrm_local_error(), from Taehee Yoo.
2) Fix return value assignments and thus error checking in
iwl_mvm_start_ap_ibss(), from Johannes Berg.
3) Don't count header length twice in vti4, from Stefano Brivio.
4) Fix deadlock in rt6_age_examine_exception, from Eric Dumazet.
5) Fix out-of-bounds access in nf_sk_lookup_slow{v4,v6}() from Subash
Abhinov.
6) Check nladdr size in netlink_connect(), from Alexander Potapenko.
7) VF representor SQ numbers are 32 not 16 bits, in mlx5 driver, from
Or Gerlitz.
8) Out of bounds read in skb_network_protocol(), from Eric Dumazet.
9) r8169 driver sets driver data pointer after register_netdev() which
is too late. Fix from Heiner Kallweit.
10) Fix memory leak in mlx4 driver, from Moshe Shemesh.
11) The multi-VLAN decap fix added a regression when dealing with device
that lack a MAC header, such as tun. Fix from Toshiaki Makita.
12) Fix integer overflow in dynamic interrupt coalescing code. From Tal
Gilboa.
13) Use after free in vrf code, from David Ahern.
14) IPV6 route leak between VRFs fix, also from David Ahern.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits)
net: mvneta: fix enable of all initialized RXQs
net/ipv6: Fix route leaking between VRFs
vrf: Fix use after free and double free in vrf_finish_output
ipv6: sr: fix seg6 encap performances with TSO enabled
net/dim: Fix int overflow
vlan: Fix vlan insertion for packets without ethernet header
net: Fix untag for vlan packets without ethernet header
atm: iphase: fix spelling mistake: "Receiverd" -> "Received"
vhost: validate log when IOTLB is enabled
qede: Do not drop rx-checksum invalidated packets.
hv_netvsc: enable multicast if necessary
ip_tunnel: Resolve ipsec merge conflict properly.
lan78xx: Crash in lan78xx_writ_reg (Workqueue: events lan78xx_deferred_multicast_write)
qede: Fix barrier usage after tx doorbell write.
vhost: correctly remove wait queue during poll failure
net/mlx4_core: Fix memory leak while delete slave's resources
net/mlx4_en: Fix mixed PFC and Global pause user control requests
net/smc: use announced length in sock_recvmsg()
llc: properly handle dev_queue_xmit() return value
strparser: Fix sign of err codes
...
nf_nat_snmp_basic_main.c includes a generated header, but the
necessary dependency is missing in Makefile. This could cause
build error in parallel building.
Remove a weird line, and add a correct one.
Fixes: cc2d58634e0f ("netfilter: nf_nat_snmp_basic: use asn1 decoder library")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Since the ORC unwinder was made the default on x86_64, Clang-built
defconfig kernels have triggered some new objtool warnings:
drivers/gpu/drm/i915/i915_gpu_error.o: warning: objtool: i915_error_printf()+0x6c: return with modified stack frame
drivers/gpu/drm/i915/intel_display.o: warning: objtool: pipe_config_err()+0xa6: return with modified stack frame
The problem is that objtool has never seen clang-built binaries before.
Shockingly enough, objtool is apparently able to follow the code flow
mostly fine, except for one instruction sequence. Instead of a LEAVE
instruction, clang restores RSP and RBP the long way:
67c: 48 89 ec mov %rbp,%rsp
67f: 5d pop %rbp
Teach objtool about this new code sequence.
Reported-and-test-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/fce88ce81c356eedcae7f00ed349cfaddb3363cc.1521741586.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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