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323f41f9 |
| 16-Dec-2015 |
Vineet Gupta <vgupta@synopsys.com> |
ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing ARC dwarf unwinder only supports CIE version == 1 The boot time dwarf sanitizer (part of binary lookup table constru
ARC: dw2 unwind: Ignore CIE version !=1 gracefully instead of bailing ARC dwarf unwinder only supports CIE version == 1 The boot time dwarf sanitizer (part of binary lookup table constructor) would simply bail if it saw CIE version == 3, rendering unwinder with a NULL lookup table. It seems libgcc linked with kernel does have such entries. With fallback linear search removed, and a NULL binary lookup table, unwinder fails to generate any stack trace. So allow graceful ignoring of unsupported CIE entries. This problem was initially seen in Alexey's setup (and not mine) as he was using buildroot built toolchain (libgcc) which doesn't get built with CFLAGS_FOR_TARGET="-gdwarf-2 which is my default Fixes STAR 9000985048: "kernel unwinder broken with stock tools" Fixes: 2e22502c080f ARC: dw2 unwind: Remove falllback linear search thru FDE entries Reported-by Alexey Brodkin <abrodkin@synopsys.com> Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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bc79c9a7 |
| 11-Dec-2015 |
Vineet Gupta <vgupta@synopsys.com> |
ARC: dw2 unwind: Reinstante unwinding out of modules The fix which removed linear searching of dwarf (because binary lookup data always exists) missed out on the fact that modules don't
ARC: dw2 unwind: Reinstante unwinding out of modules The fix which removed linear searching of dwarf (because binary lookup data always exists) missed out on the fact that modules don't get the binary lookup tables info. This caused unwinding out of modules to stop working. So add binary lookup header setup (equivalent of eh_frame_hdr setup) to modules as well. While at it, confine the header setup to within unwinder code, reducing one API exposed out of unwinder code. Fixes: 2e22502c080f ARC: dw2 unwind: Remove falllback linear search thru FDE entries Cc: <stable@vger.kernel.org> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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7523e4dc |
| 25-Nov-2015 |
Rusty Russell <rusty@rustcorp.com.au> |
module: use a structure to encapsulate layout. Makes it easier to handle init vs core cleanly, though the change is fairly invasive across random architectures. It simplifies th
module: use a structure to encapsulate layout. Makes it easier to handle init vs core cleanly, though the change is fairly invasive across random architectures. It simplifies the rbtree code immediately, however, while keeping the core data together in the same cachline (now iff the rbtree code is enabled). Acked-by: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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2e22502c |
| 23-Nov-2015 |
Vineet Gupta <vgupta@synopsys.com> |
ARC: dw2 unwind: Remove falllback linear search thru FDE entries Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls" | perf record -g -c 15000 -e cycles /sbin/hackb
ARC: dw2 unwind: Remove falllback linear search thru FDE entries Fixes STAR 9000953410: "perf callgraph profiling causing RCU stalls" | perf record -g -c 15000 -e cycles /sbin/hackbench | | INFO: rcu_preempt self-detected stall on CPU | 1: (1 GPs behind) idle=609/140000000000002/0 softirq=2914/2915 fqs=603 | Task dump for CPU 1: in-kernel dwarf unwinder has a fast binary lookup and a fallback linear search (which iterates thru each of ~11K entries) thus takes 2 orders of magnitude longer (~3 million cycles vs. 2000). Routines written in hand assembler lack dwarf info (as we don't support assembler CFI pseudo-ops yet) fail the unwinder binary lookup, hit linear search, failing nevertheless in the end. However the linear search is pointless as binary lookup tables are created from it in first place. It is impossible to have binary lookup fail while succeed the linear search. It is pure waste of cycles thus removed by this patch. This manifested as RCU stalls / NMI watchdog splat when running hackbench under perf with callgraph profiling. The triggering condition was perf counter overflowing in routine lacking dwarf info (like memset) leading to patheic 3 million cycle unwinder slow path and by the time it returned new interrupts were already pending (Timer, IPI) and taken rightaway. The original memset didn't make forward progress, system kept accruing more interrupts and more unwinder delayes in a vicious feedback loop, ultimately triggering the NMI diagnostic. Cc: stable@vger.kernel.org Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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d939be3a |
| 27-Feb-2015 |
Masanari Iida <standby24x7@gmail.com> |
treewide: Fix typo in printk messages This patch fix spelling typo in printk messages. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infra
treewide: Fix typo in printk messages This patch fix spelling typo in printk messages. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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baadb8fd |
| 25-Jun-2013 |
Vineet Gupta <vgupta@synopsys.com> |
ARC: warn on improper stack unwind FDE entries Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
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Revision tags: v3.10-rc7, v3.10-rc6, v3.10-rc5, v3.10-rc4, v3.10-rc3, v3.10-rc2, v3.10-rc1, v3.9, v3.9-rc8, v3.9-rc7, v3.9-rc6, v3.9-rc5, v3.9-rc4, v3.9-rc3, v3.9-rc2, v3.9-rc1, v3.8, v3.8-rc7, v3.8-rc6, v3.8-rc5 |
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854a0d95 |
| 22-Jan-2013 |
Vineet Gupta <vgupta@synopsys.com> |
ARC: DWARF2 .debug_frame based stack unwinder -Originally written by Rajeshwar Ranga -Derived off of generic unwinder in 2.6.19 and adapted to ARC Signed-off-by: Vineet Gupta <v
ARC: DWARF2 .debug_frame based stack unwinder -Originally written by Rajeshwar Ranga -Derived off of generic unwinder in 2.6.19 and adapted to ARC Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
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