Re: [PATCH v7 1/2] Kbuild: make DWARF version a choice

Hi Nick, On Fri, Feb 05, 2021 at 01:18:11PM -0800, Nick Desaulniers wrote: > On Fri, Feb 5, 2021 at 4:49 AM Mark Wielaard wrote: > I guess I'm curious whether > https://bugzilla.redhat.com/show_bug.cgi?id=1922707 came up during the > mass rebuild of all of Fedora a few weeks ag

Re: [PATCH v9 1/3] vmlinux.lds.h: add DWARF v5 sections

Hi Nick, On Fri, 2021-02-05 at 12:22 -0800, Nick Desaulniers wrote: > We expect toolchains to produce these new debug info sections as part of > DWARF v5. Add explicit placements to prevent the linker warnings from > --orphan-section=warn. > > Compilers may produce such sections with explicit

Re: [PATCH v7 1/2] Kbuild: make DWARF version a choice

Hi Nick, On Thu, 2021-02-04 at 14:06 -0800, Nick Desaulniers wrote: > On Thu, Feb 4, 2021 at 12:28 PM Mark Wielaard wrote: > > I believe so yes, we did a mass-rebuild of all of Fedora a few weeks > > back with a GCC11 pre-release and did find some tools which weren't > > r

Re: [PATCH v7 1/2] Kbuild: make DWARF version a choice

On Thu, 2021-02-04 at 12:04 -0800, Nick Desaulniers wrote: > On Thu, Feb 4, 2021 at 11:56 AM Mark Wielaard wrote: > > I agree with Jakub. Now that GCC has defaulted to DWARF5 all the > > tools > > have adopted to the new default version. And DWARF5 has been out > >

Re: [PATCH v7 1/2] Kbuild: make DWARF version a choice

On Thu, 2021-02-04 at 11:18 -0800, Nick Desaulniers wrote: > On Thu, Feb 4, 2021 at 2:41 AM Mark Wielaard wrote: > > On Fri, Jan 29, 2021 at 04:44:00PM -0800, Nick Desaulniers wrote: > > > Modifies CONFIG_DEBUG_INFO_DWARF4 to be a member of a choice which is > > > th

Re: [PATCH v7 1/2] Kbuild: make DWARF version a choice

Hi Nick, On Fri, Jan 29, 2021 at 04:44:00PM -0800, Nick Desaulniers wrote: > Modifies CONFIG_DEBUG_INFO_DWARF4 to be a member of a choice which is > the default. Does so in a way that's forward compatible with existing > configs, and makes adding future versions more straightforward. > > GCC

Re: [PATCH] kbuild: fix duplicated flags in DEBUG_CFLAGS

cking-assignments)) > +DEBUG_CFLAGS += $(call cc-ifversion, -lt, 0500, $(call cc-option, > -fno-var-tracking-assignments)) > endif Yes, this makes sense given that the original code, before commit 121c5d08d53c did always set DEBUG_CFLAGS without checking for CONFIG_CC_IS_GCC. So it beh

Re: [PATCH] syscalls: Document OCI seccomp filter interactions & workaround

Hi, Just a reply to note that this isn't just an issue for glibc, but for any program that might use linux syscalls directly (with fallbacks). On Tue, 2020-11-24 at 13:54 +0100, Florian Weimer wrote: > > I agree that the standard should mandate ENOSYS, and I've just proposed > a specification

Re: Additional debug info to aid cacheline analysis

Hi Namhyung, On Fri, Oct 30, 2020 at 02:26:19PM +0900, Namhyung Kim wrote: > On Thu, Oct 8, 2020 at 6:38 PM Mark Wielaard wrote: > > GCC using -fvar-tracking and -fvar-tracking-assignments is pretty good > > at keeping track of where variables are held (in memory or regi

[PATCH V2] Only add -fno-var-tracking-assignments workaround for old GCC versions.

in ifdef CONFIG_CC_IS_GCC Signed-off-by: Mark Wielaard Acked-by: Ian Rogers Reviewed-by: Andi Kleen Cc: linux-toolcha...@vger.kernel.org Cc: Nick Desaulniers Cc: Segher Boessenkool Cc: Florian Weimer Cc: Sedat Dilek --- Makefile | 6 +- 1 file changed, 5 insertions(+), 1 deletion

[PATCH] Only add -fno-var-tracking-assignments workaround for old GCC versions.

it for versions of GCC before 5.0. Signed-off-by: Mark Wielaard Acked-by: Ian Rogers Cc: linux-toolcha...@vger.kernel.org Cc: Andi Kleen Cc: Nick Desaulniers Cc: Segher Boessenkool Cc: Florian Weimer --- Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Makefile b

Re: [PATCH] Only add -fno-var-tracking-assignments workaround for old GCC versions.

Hi, On Mon, 2020-10-12 at 11:59 -0700, Nick Desaulniers wrote: > On Sat, Oct 10, 2020 at 3:57 PM Ian Rogers > wrote: > > On Sat, Oct 10, 2020 at 3:08 PM Mark Wielaard > > wrote: > > > -DEBUG_CFLAGS := $(call cc-option, -fno-var-tracking- > > > as

Re: Additional debug info to aid cacheline analysis

On Sun, Oct 11, 2020 at 02:15:18PM +0200, Florian Weimer wrote: > * Mark Wielaard: > > > Yes, that would work. I don't know what the lowest supported GCC > > version is, but technically it was definitely fixed in 4.10.0, 4.8.4 > > and 4.9.2. And various distros would

Re: Additional debug info to aid cacheline analysis

ackported the fix. But checking for 5.0+ would certainly give you a good version. How about the attached? Cheers, Mark>From 48628d3cf2d829a90cd6622355eada1b30cb10c1 Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Sat, 10 Oct 2020 22:47:21 +0200 Subject: [PATCH] Only add -fno-var-tracking-as

[PATCH] Only add -fno-var-tracking-assignments workaround for old GCC versions.

it for versions of GCC before 5.0. Signed-off-by: Mark Wielaard --- Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/Makefile b/Makefile index f84d7e4ca0be..4f4a9416a87a 100644 --- a/Makefile +++ b/Makefile @@ -813,7 +813,9 @@ KBUILD_CFLAGS += -ftrivial-auto-var

Re: Additional debug info to aid cacheline analysis

On Sat, Oct 10, 2020 at 10:58:36PM +0200, Mark Wielaard wrote: > Yes, that would work. I don't know what the lowest supported GCC > version is, but technically it was definitely fixed in 4.10.0, 4.8.4 > and 4.9.2. And various distros would probably have backported the > fix. But chec

Re: Additional debug info to aid cacheline analysis

Hi, On Thu, 2020-10-08 at 09:02 +0200, Peter Zijlstra wrote: > Some time ago, I had my intern pursue the other 2 approaches for > > symbolization. The one I see as most promising is by using the DWARF > > information (no BPF needed). The good news is that I believe we do not > > need more

Re: Static call dependency on libelf version?

Hi Josh, On Tue, 2020-09-15 at 09:17 -0500, Josh Poimboeuf wrote: > On Tue, Sep 15, 2020 at 01:24:17PM +0200, Mark Wielaard wrote: > > But all this is for ancient versions of elfutils libelf. So it is hard > > to say and my memory might be failing. If someone can confirm 0.158

Re: Static call dependency on libelf version?

rs old. Given that 0.168 (4 years old) works fine and this might be an interaction with objtool, which if I remember correctly uses ELF_C_RDWR to manipulate an ELF file in place, I suspect it might be: commit 88ad5ddb71bd1fa8ed043a840157ebf23c0057b3 Author: Mark Wielaard Date: Tue Nov 5 16:27:32 2

Re: Kernel build error on BTFIDS vmlinux

d it would be nice if binutils ld could also be fixed to set the sh_addralign field correctly. Cheers, Mark From 55c5c9a568ed707bcea1388bf3a525212d8cf4b8 Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Wed, 19 Aug 2020 23:41:24 +0200 Subject: [PATCH] libelf: Fixup SHF_COMPRESSED sh_addralign in elf

Re: Kernel build error on BTFIDS vmlinux

Hi, Adding Nick, the binutils maintainer, so we can make sure binutils/elfutils agree on some ELF section compression corner case. On Tue, 2020-08-18 at 18:33 +0200, Jesper Dangaard Brouer wrote: > On Tue, 18 Aug 2020 15:45:43 +0200 > Jiri Olsa wrote: > > > On Tue, Aug 18, 2020 at 12:56:08PM

Re: sendmmsg flags userspace ABI change in kernel 4.6

Hi, Adding valgrind-developers to CC. On Wed, 2018-04-18 at 21:03 +0200, Florian Weimer wrote: > Since this commit: > > commit 28a94d8fb35b3a75b802f368ae6f4a9f6b0d435a > Author: Tom Herbert > Date:   Mon Mar 7 14:11:02 2016 -0800 > > net: Allow MSG_EOR in each msghdr

Re: sendmmsg flags userspace ABI change in kernel 4.6

Hi, Adding valgrind-developers to CC. On Wed, 2018-04-18 at 21:03 +0200, Florian Weimer wrote: > Since this commit: > > commit 28a94d8fb35b3a75b802f368ae6f4a9f6b0d435a > Author: Tom Herbert > Date:   Mon Mar 7 14:11:02 2016 -0800 > > net: Allow MSG_EOR in each msghdr of sendmmsg > >

Re: perf probe line numbers + CONFIG_DEBUG_INFO_SPLIT=y

On Wed, 2018-04-18 at 23:03 +0900, Masami Hiramatsu wrote: > It shows where we can see the .dwo file. > However, it seems elfutils doesn't support dwo. > > $ eu-readelf --debug-dump=info ~/kbin/linux.x86_64/fs/namei.dwo  > eu-readelf: cannot get debug context descriptor: No DWARF information >

Re: perf probe line numbers + CONFIG_DEBUG_INFO_SPLIT=y

On Wed, 2018-04-18 at 23:03 +0900, Masami Hiramatsu wrote: > It shows where we can see the .dwo file. > However, it seems elfutils doesn't support dwo. > > $ eu-readelf --debug-dump=info ~/kbin/linux.x86_64/fs/namei.dwo  > eu-readelf: cannot get debug context descriptor: No DWARF information >

Re: [RFCv2 PATCH 0/3] Salted build ids via linker sections

On Thu, 2018-03-29 at 11:01 -0700, Laura Abbott wrote: > I'm still mostly looking for feedback whether > this would be acceptable for merging or if we should just persue a > --build-id-salt in binutils. Personally I would go with this approach. It seems simple and it might take years before a new

Re: [RFCv2 PATCH 0/3] Salted build ids via linker sections

On Thu, 2018-03-29 at 11:01 -0700, Laura Abbott wrote: > I'm still mostly looking for feedback whether > this would be acceptable for merging or if we should just persue a > --build-id-salt in binutils. Personally I would go with this approach. It seems simple and it might take years before a new

Re: [RFC PATCH 0/3] Salted build ids via linker sections

ding issue where only > > one > > version of a debuginfo info package can be installed at a time. Mark > > Wielaard > > made an effort for Fedora 27 to allow parallel installation of debuginfo > > (see > > https://fedoraproject.org/wiki/Changes/ParallelInstall

Re: [RFC PATCH 0/3] Salted build ids via linker sections

> one > > version of a debuginfo info package can be installed at a time. Mark > > Wielaard > > made an effort for Fedora 27 to allow parallel installation of debuginfo > > (see > > https://fedoraproject.org/wiki/Changes/ParallelInstallableDebuginfo for >

Re: [PATCH v2] perf: libdw support for powerpc [ping]

On Tue, Jun 20, 2017 at 10:06:35PM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, Jun 15, 2017 at 01:16:32PM +0200, Mark Wielaard escreveu: > > On Thu, 2017-06-15 at 10:46 +0200, Milian Wolff wrote: > > > Just a quick question: Have you guys applied my recent patch: &

Re: [PATCH v2] perf: libdw support for powerpc [ping]

On Tue, Jun 20, 2017 at 10:06:35PM -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, Jun 15, 2017 at 01:16:32PM +0200, Mark Wielaard escreveu: > > On Thu, 2017-06-15 at 10:46 +0200, Milian Wolff wrote: > > > Just a quick question: Have you guys applied my recent patch: &

Re: [PATCH v2] perf: libdw support for powerpc [ping]

On Thu, 2017-06-15 at 10:46 +0200, Milian Wolff wrote: > Just a quick question: Have you guys applied my recent patch: > > commit 5ea0416f51cc93436bbe497c62ab49fd9cb245b6 > Author: Milian Wolff > Date: Thu Jun 1 23:00:21 2017 +0200 > > perf report: Include partial

Re: [PATCH v2] perf: libdw support for powerpc [ping]

On Thu, 2017-06-15 at 10:46 +0200, Milian Wolff wrote: > Just a quick question: Have you guys applied my recent patch: > > commit 5ea0416f51cc93436bbe497c62ab49fd9cb245b6 > Author: Milian Wolff > Date: Thu Jun 1 23:00:21 2017 +0200 > > perf report: Include partial stacks unwound with

Re: [PATCH v2] perf: libdw support for powerpc [ping]

Hi Ravi, On Mon, 2017-06-12 at 17:28 +0530, Ravi Bangoria wrote: > So, I tested this patch along with Mark's patch[1] on elfutils an looks > like it's not working. Steps on what I did: > > After applying Mark's patch on upstream elfutils: > > $ aclocal > $ autoheader > $ autoconf > $

Re: [PATCH v2] perf: libdw support for powerpc [ping]

Hi Ravi, On Mon, 2017-06-12 at 17:28 +0530, Ravi Bangoria wrote: > So, I tested this patch along with Mark's patch[1] on elfutils an looks > like it's not working. Steps on what I did: > > After applying Mark's patch on upstream elfutils: > > $ aclocal > $ autoheader > $ autoconf > $

Re: [PATCH] perf/probe: Search both .eh_frame and .debug_frame sections for probe location

On Thu, 2015-09-24 at 10:56 +, 平松雅巳 / HIRAMATU，MASAMI wrote: > >I am not too familiar with the code so there might be a reason for > >setting and reusing the pf->cfi to do the search twice. But might it not > >be more clear to just store both pf->cfi_eh and pf->cfi_debug and then > >check both

Re: [PATCH] perf/probe: Search both .eh_frame and .debug_frame sections for probe location

Hi Hemant, On Thu, 2015-09-24 at 07:46 +0530, Hemant Kumar wrote: > perf probe through debuginfo__find_probes() in util/probe-finder.c > checks for the functions' frame descriptions in either .eh_frame section > of an ELF or the .debug_frame. The check is based on whether either one > of these

Re: [PATCH] perf/probe: Search both .eh_frame and .debug_frame sections for probe location

Hi Hemant, On Thu, 2015-09-24 at 07:46 +0530, Hemant Kumar wrote: > perf probe through debuginfo__find_probes() in util/probe-finder.c > checks for the functions' frame descriptions in either .eh_frame section > of an ELF or the .debug_frame. The check is based on whether either one > of these

Re: [PATCH] perf/probe: Search both .eh_frame and .debug_frame sections for probe location

On Thu, 2015-09-24 at 10:56 +, 平松雅巳 / HIRAMATU，MASAMI wrote: > >I am not too familiar with the code so there might be a reason for > >setting and reusing the pf->cfi to do the search twice. But might it not > >be more clear to just store both pf->cfi_eh and pf->cfi_debug and then > >check both

Re: perf-probe crash in dwarf_getcfi_elf

On Tue, Dec 30, 2014 at 06:05:33PM +0900, Namhyung Kim wrote: > And I found a related commit (5704c8c4fa71 "getcfi_scn_eh_frame: Don't > crash and burn when .eh_frame bits aren't there.") in elfutils that > can lead to a unexpected crash like this. To safely use the function, > it needs to check

Re: perf-probe crash in dwarf_getcfi_elf

On Tue, Dec 30, 2014 at 06:05:33PM +0900, Namhyung Kim wrote: And I found a related commit (5704c8c4fa71 getcfi_scn_eh_frame: Don't crash and burn when .eh_frame bits aren't there.) in elfutils that can lead to a unexpected crash like this. To safely use the function, it needs to check the

Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Thu, 2013-10-31 at 11:57 +0100, Ingo Molnar wrote: > * Mark Wielaard wrote: > > On Wed, 2013-10-30 at 13:51 +0200, Pekka Enberg wrote: > > > On 10/30/13 12:05 PM, Masami Hiramatsu wrote: > > > > To find all system libraries, we can use ldconfig. > >

Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Wed, 2013-10-30 at 13:51 +0200, Pekka Enberg wrote: > On 10/30/13 12:05 PM, Masami Hiramatsu wrote: > > To find all system libraries, we can use ldconfig. > > > > $ ldconfig --print-cache > > > > shows what dynamic libraries will be loaded. On my own laptop (running > > ubuntu13.04) shows ~1000

Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Wed, 2013-10-30 at 13:51 +0200, Pekka Enberg wrote: On 10/30/13 12:05 PM, Masami Hiramatsu wrote: To find all system libraries, we can use ldconfig. $ ldconfig --print-cache shows what dynamic libraries will be loaded. On my own laptop (running ubuntu13.04) shows ~1000 libs.

Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Thu, 2013-10-31 at 11:57 +0100, Ingo Molnar wrote: * Mark Wielaard m...@redhat.com wrote: On Wed, 2013-10-30 at 13:51 +0200, Pekka Enberg wrote: On 10/30/13 12:05 PM, Masami Hiramatsu wrote: To find all system libraries, we can use ldconfig. $ ldconfig --print-cache

Re: Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Tue, 2013-10-29 at 12:19 +0900, Masami Hiramatsu wrote: > (2013/10/29 2:48), Pekka Enberg wrote: > > For the 32-bit and 64-bit libc case, why cannot 'perf list' > > by default print out something like: > > > > $ perf list > > > >libc:setjmp [SDT marker group] > > > > and provide a

Re: Re: [PATCH v4 2/3] Support for perf to probe into SDT markers:

On Tue, 2013-10-29 at 12:19 +0900, Masami Hiramatsu wrote: (2013/10/29 2:48), Pekka Enberg wrote: For the 32-bit and 64-bit libc case, why cannot 'perf list' by default print out something like: $ perf list libc:setjmp [SDT marker group] and provide a '--fully-qualified'

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Wed, 2013-09-04 at 23:42 +0530, Hemant wrote: > On 09/04/2013 01:55 PM, Mark Wielaard wrote: > > Note that if you use the normal DTRACE_PROBE macros no semaphore will be > > inserted. And you can opt to not support probes that have a semaphore in > > perf if you think that

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Wed, 2013-09-04 at 15:49 +0900, Namhyung Kim wrote: > On Tue, 03 Sep 2013 18:53:17 +0530, Hemant wrote: > > On 09/03/2013 02:47 PM, Masami Hiramatsu wrote: > >> Indeed, and also I'd like to know what versions of SDT this support, > >> and where we can see the technical document of that. As far

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Wed, 2013-09-04 at 15:49 +0900, Namhyung Kim wrote: On Tue, 03 Sep 2013 18:53:17 +0530, Hemant wrote: On 09/03/2013 02:47 PM, Masami Hiramatsu wrote: Indeed, and also I'd like to know what versions of SDT this support, and where we can see the technical document of that. As far as I

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Wed, 2013-09-04 at 23:42 +0530, Hemant wrote: On 09/04/2013 01:55 PM, Mark Wielaard wrote: Note that if you use the normal DTRACE_PROBE macros no semaphore will be inserted. And you can opt to not support probes that have a semaphore in perf if you think that is easier (just check

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Tue, 2013-09-03 at 16:21 +0200, Ingo Molnar wrote: > * Hemant wrote: > > > Here is an overview and a high-level-description: > > Thanks, looks like a pretty useful feature - especially if SDT probes are > already widely present in various server binaries on a typical Linux > distro (are

Re: [RFC PATCH 0/2] Perf support to SDT markers

On Tue, 2013-09-03 at 16:21 +0200, Ingo Molnar wrote: * Hemant hks...@linux.vnet.ibm.com wrote: Here is an overview and a high-level-description: Thanks, looks like a pretty useful feature - especially if SDT probes are already widely present in various server binaries on a typical Linux

Re: [PATCH -tip ] [BUGFIX] perf probe: Add a workaround for GCC -mfentry

On Wed, 2012-10-03 at 09:53 -0400, Steven Rostedt wrote: > On Wed, 2012-10-03 at 21:17 +0900, Masami Hiramatsu wrote: > > <1><9a58>: Abbrev Number: 86 (DW_TAG_subprogram) > > <9a59> DW_AT_external: 1 > > <9a59> DW_AT_name: (indirect string, offset: 0xd82): > >

Re: [PATCH -tip ] [BUGFIX] perf probe: Add a workaround for GCC -mfentry

On Wed, 2012-10-03 at 09:53 -0400, Steven Rostedt wrote: On Wed, 2012-10-03 at 21:17 +0900, Masami Hiramatsu wrote: 19a58: Abbrev Number: 86 (DW_TAG_subprogram) 9a59 DW_AT_external: 1 9a59 DW_AT_name: (indirect string, offset: 0xd82): unregister_di e_notifier