Since commit:
4bcc595ccd "printk: reinstate KERN_CONT for printing"
... the debug output of signal_fault(), do_trap() and do_general_protection()
looks garbled, e.g.:
traps: conftest[9335] trap invalid opcode ip:400428 sp:7ffeaba1b0d8 error:0
in conftest[400000+1000]
(note the unintended line break.)
Fix the bug by adding KERN_CONTs.
Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's a conflict between ongoing level-5 paging support and
the E820 rewrite. Since the E820 rewrite is essentially ready,
merge it into x86/mm to reduce tree conflicts.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The E820 rework in WIP.x86/boot has gone through a couple of weeks
of exposure in -tip, merge it in a wider fashion.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The resource control filesystem provides only a bitmask based cpus file for
assigning CPUs to a resource group. That's cumbersome with large cpumasks
and non-intuitive when modifying the file from the command line.
Range based cpu lists are commonly used along with bitmask based cpu files
in various subsystems throughout the kernel.
Add 'cpus_list' file which is CPU range based.
# cd /sys/fs/resctrl/
# echo 1-10 > krava/cpus_list
# cat krava/cpus_list
1-10
# cat krava/cpus
0007fe
# cat cpus
fffff9
# cat cpus_list
0,3-23
[ tglx: Massaged changelog and replaced "bitmask lists" by "CPU ranges" ]
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Shaohua Li <shli@fb.com>
Link: http://lkml.kernel.org/r/20170410145232.GF25354@krava
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Apparently, some machines used to report DRAM errors through a PCI SERR
NMI. This is why we have a call into EDAC in the NMI handler. See
c0d1217202 ("drivers/edac: add new nmi rescan").
From looking at the patch above, that's two drivers: e752x_edac.c and
e7xxx_edac.c. Now, I wanna say those are old machines which are probably
decommissioned already.
Tony says that "[t]the newest CPU supported by either of those drivers
is the Xeon E7520 (a.k.a. "Nehalem") released in Q1'2010. Possibly some
folks are still using these ... but people that hold onto h/w for 7
years generally cling to old s/w too ... so I'd guess it unlikely that
we will get complaints for breaking these in upstream."
So even if there is a small number still in use, we did load EDAC with
edac_op_state == EDAC_OPSTATE_POLL by default (we still do, in fact)
which means a default EDAC setup without any parameters supplied on the
command line or otherwise would never even log the error in the NMI
handler because we're polling by default:
inline int edac_handler_set(void)
{
if (edac_op_state == EDAC_OPSTATE_POLL)
return 0;
return atomic_read(&edac_handlers);
}
So, long story short, I'd like to get rid of that nastiness called
edac_stub.c and confine all the EDAC drivers solely to drivers/edac/. If
we ever have to do stuff like that again, it should be notifiers we're
using and not some insanity like this one.
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
When auto EOI is not enabled; issue an explicit EOI for hyper-v
interrupts.
Fixes: 6c248aad81 ("Drivers: hv: Base autoeoi enablement based on hypervisor hints")
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull RAS fix from Thomas Gleixner:
"Prevent dmesg from being spammed when MCE logging is active"
* 'ras-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mce: Don't print MCEs when mcelog is active
The kbuild test robot reported this build failure on a number
of architectures:
> make.cross ARCH=arm
> lib/lib.a(bug.o): In function `find_bug':
> >> lib/bug.c:135: undefined reference to `__start___bug_table'
> >> lib/bug.c:135: undefined reference to `__stop___bug_table'
Caused by:
19d436268d ("debug: Add _ONCE() logic to report_bug()")
Which moved the BUG_TABLE from RO_DATA_SECTION() to RW_DATA_SECTION(),
but a number of architectures don't use RW_DATA_SECTION(), so they
ended up with no __bug_table[] ...
Ideally all those would use RW_DATA_SECTION() in their linker scripts,
but that's for another day.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Link: http://lkml.kernel.org/r/20170330154927.o6qmgfp4bdhrajbm@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 fixes from Thomas Gleixner:
"This update provides:
- prevent KASLR from randomizing EFI regions
- restrict the usage of -maccumulate-outgoing-args and document when
and why it is required.
- make the Global Physical Address calculation for UV4 systems work
correctly.
- address a copy->paste->forgot-edit problem in the MCE exception
table entries.
- assign a name to AMD MCA bank 3, so the sysfs file registration
works.
- add a missing include in the boot code"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Include missing header file
x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs
x86/build: Mostly disable '-maccumulate-outgoing-args'
x86/mm/KASLR: Exclude EFI region from KASLR VA space randomization
x86/mce: Fix copy/paste error in exception table entries
x86/platform/uv: Fix calculation of Global Physical Address
The x86 mmap() code selects the mmap base for an allocation depending on
the bitness of the syscall. For 64bit sycalls it select mm->mmap_base and
for 32bit mm->mmap_compat_base.
On execve the registers of the task invoking exec() are copied to the child
pt_regs. So child->pt_regs->orig_ax contains the execve syscall number of the
parent.
exec() calls mmap() which in turn uses in_compat_syscall() to check whether
the mapping is for a 32bit or a 64bit task. The decision is made on the
following criteria:
ia32 child->thread.status & TS_COMPAT
x32 child->pt_regs.orig_ax & __X32_SYSCALL_BIT
ia64 !ia32 && !x32
child->thread.status is corretly set up in set_personality_*(), but the
syscall number in child->pt_regs.orig_ax is left unmodified.
Therefore the parent/child combinations work or fail in the following way:
Parent Child Child->thread_status child->pt_regs.orig_ax in_compat() Works
ia64 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false Y
ia64 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 0 true Y
ia64 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false N
ia32 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false Y
ia32 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 0 true Y
ia32 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 0 false N
x32 ia64 TS_COMPAT == 0 __X32_SYSCALL_BIT == 1 true N
x32 ia32 TS_COMPAT == 1 __X32_SYSCALL_BIT == 1 true Y
x32 x32 TS_COMPAT == 0 __X32_SYSCALL_BIT == 1 true Y
Make set_personality_*() store the syscall number incl. __X32_SYSCALL_BIT
which corresponds to the newly started ELF executable in the childs
pt_regs, i.e. pretend that the exec was invoked from a task with the same
executable format.
So both thread.status and pt_regs.orig_ax correspond to the new ELF format
and in_compat_syscall() returns the correct result.
[ tglx: Rewrote changelog ]
Fixes: commit 1b028f784e ("x86/mm: Introduce mmap_compat_base() for 32-bit mmap()")
Reported-by: Adam Borowski <kilobyte@angband.pl>
Suggested-by: H. Peter Anvin <hpa@zytor.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com>
Cc: 0x7f454c46@gmail.com
Cc: linux-mm@kvack.org
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: http://lkml.kernel.org/r/20170331111137.28170-1-dsafonov@virtuozzo.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name.
However, MCA bank 3 is defined on Fam17h systems and can be accessed
using legacy MSRs. Without a name we get a stack trace on Fam17h systems
when trying to register sysfs files for bank 3 on kernels that don't
recognize Scalable MCA.
Call MCA bank 3 "decode_unit" since this is what it represents on
Fam17h. This will allow kernels without SMCA support to see this bank on
Fam17h+ and prevent the stack trace. This will not affect older systems
since this bank is reserved on them, i.e. it'll be ignored.
Tested on AMD Fam15h and Fam17h systems.
WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal
kobject: (ffff88085bb256c0): attempted to be registered with empty name!
...
Call Trace:
kobject_add_internal
kobject_add
kobject_create_and_add
threshold_create_device
threshold_init_device
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The GCC '-maccumulate-outgoing-args' flag is enabled for most configs,
mostly because of issues which are no longer relevant. For most
configs, and with most recent versions of GCC, it's no longer needed.
Clarify which cases need it, and only enable it for those cases. Also
produce a compile-time error for the ftrace graph + mcount + '-Os' case,
which will otherwise cause runtime failures.
The main benefit of '-maccumulate-outgoing-args' is that it prevents an
ugly prologue for functions which have aligned stacks. But removing the
option also has some benefits: more readable argument saves, smaller
text size, and (presumably) slightly improved performance.
Here are the object size savings for 32-bit and 64-bit defconfig
kernels:
text data bss dec hex filename
10006710 3543328 1773568 15323606 e9d1d6 vmlinux.x86-32.before
9706358 3547424 1773568 15027350 e54c96 vmlinux.x86-32.after
text data bss dec hex filename
10652105 4537576 843776 16033457 f4a6b1 vmlinux.x86-64.before
10639629 4537576 843776 16020981 f475f5 vmlinux.x86-64.after
That comes out to a 3% text size improvement on x86-32 and a 0.1% text
size improvement on x86-64.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170316193133.zrj6gug53766m6nn@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Moving enabling of function tracing to early boot, even before scheduling is
enabled, means that it is not safe to enable interrupts. When function
tracing was enabled at boot up, it use to happen after scheduling and the
other CPUs were brought up. That required running a sync across all CPUs
when modifying the function hook locations in the code. To do the
synchronization, interrupts had to be enabled. Now function tracing can be
started before the other CPUs are brought up, and enabling interrupts in
that case is dangerous. As only tho boot CPU is active, there is no reason
to run the synchronization. If the online CPU count is one, do not bother
doing the synchronization. This removes the need to enable interrupts.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Introduce a simple data structure for collecting correctable errors
along with accessors. More detailed description in the code itself.
The error decoding is done with the decoding chain now and
mce_first_notifier() gets to see the error first and the CEC decides
whether to log it and then the rest of the chain doesn't hear about it -
basically the main reason for the CE collector - or to continue running
the notifiers.
When the CEC hits the action threshold, it will try to soft-offine the
page containing the ECC and then the whole decoding chain gets to see
the error.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170327093304.10683-5-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
By using "UD0" for WARN()s we remove the function call and its possible
__FILE__ and __LINE__ immediate arguments from the instruction stream.
Total image size will not change much, what we win in the instruction
stream we'll lose because of the __bug_table entries. Still, saves on
I$ footprint and the total image size does go down a bit.
text data filename
10702123 4530992 defconfig-build/vmlinux.orig
10682460 4530992 defconfig-build/vmlinux.patched
(UML didn't seem to use GENERIC_BUG at all, so remove it)
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Weinberger <richard.weinberger@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86_64 has had fentry support for some time. I did not add support to x86_32
as I was unsure if it will be used much in the future. It is still very much
used, and there's issues with function graph tracing with gcc playing around
with the mcount frames, causing function graph to panic. The fentry code
does not have this issue, and is able to cope as there is no frame to mess
up.
Note, this only adds support for fentry when DYNAMIC_FTRACE is set. There's
really no reason to not have that set, because the performance of the
machine drops significantly when it's not enabled.
Keep !DYNAMIC_FTRACE around to test it off, as there's still some archs
that have FTRACE but not DYNAMIC_FTRACE.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20170323143446.052202377@goodmis.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
