All of lore.kernel.org
 help / color / mirror / Atom feed
From: Mark Rutland <mark.rutland@arm.com>
To: Alexander Potapenko <glider@google.com>
Cc: linux-arm-kernel@lists.infradead.org,
	Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	marc.zyngier@arm.com, Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	LKML <linux-kernel@vger.kernel.org>,
	Quentin Casasnovas <quentin.casasnovas@oracle.com>,
	Kostya Serebryany <kcc@google.com>,
	syzkaller <syzkaller@googlegroups.com>,
	Christoffer Dall <christoffer.dall@linaro.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Dmitriy Vyukov <dvyukov@google.com>
Subject: Re: [PATCH v2] arm64: allow building with kcov coverage on ARM64
Date: Wed, 15 Jun 2016 12:44:39 +0100	[thread overview]
Message-ID: <20160615114438.GC3984@leverpostej> (raw)
In-Reply-To: <20160615092509.GA3984@leverpostej>

On Wed, Jun 15, 2016 at 10:25:10AM +0100, Mark Rutland wrote:
> On Tue, Jun 14, 2016 at 08:16:08PM +0200, Alexander Potapenko wrote:
> > On Tue, Jun 14, 2016 at 7:55 PM, Mark Rutland <mark.rutland@arm.com> wrote:
> > > I built and booted (via EFI) a kernel with this feature enabled (also
> > > with the boot/Makefile change removed). I haven't tested the feature
> > > itself as such, as I'm not sure how to do that.
> > You can test it by running the test program from Documentation/kcov.txt.
> 
> Ah, I hadn't spotted that. If I get the chance I'll try to give that a
> go.

I just had a go (with this applied atop of v4.7-rc3), and I get:

root@ribbensteg:/home/nanook# ./kcov 
mmap: No such device

The device exists (it was able to open the fd, evidently):

root@ribbensteg:/home/nanook# ls -al /sys/kernel/debug/kcov 
-rw------- 1 root root 0 Jan  1  1970 /sys/kernel/debug/kcov

Strace show me:

openat(AT_FDCWD, "/sys/kernel/debug/kcov", O_RDWR) = 3
ioctl(3, CHIOMOVE or CM_IOCGATR, 0x10000) = 0
mmap(NULL, 524288, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = -1 ENODEV (No such device)

It doesn't look like the error paths in kcov_mmap are hitting.

Any ideas?

Thanks,
Mark.

WARNING: multiple messages have this Message-ID (diff)
From: mark.rutland@arm.com (Mark Rutland)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2] arm64: allow building with kcov coverage on ARM64
Date: Wed, 15 Jun 2016 12:44:39 +0100	[thread overview]
Message-ID: <20160615114438.GC3984@leverpostej> (raw)
In-Reply-To: <20160615092509.GA3984@leverpostej>

On Wed, Jun 15, 2016 at 10:25:10AM +0100, Mark Rutland wrote:
> On Tue, Jun 14, 2016 at 08:16:08PM +0200, Alexander Potapenko wrote:
> > On Tue, Jun 14, 2016 at 7:55 PM, Mark Rutland <mark.rutland@arm.com> wrote:
> > > I built and booted (via EFI) a kernel with this feature enabled (also
> > > with the boot/Makefile change removed). I haven't tested the feature
> > > itself as such, as I'm not sure how to do that.
> > You can test it by running the test program from Documentation/kcov.txt.
> 
> Ah, I hadn't spotted that. If I get the chance I'll try to give that a
> go.

I just had a go (with this applied atop of v4.7-rc3), and I get:

root at ribbensteg:/home/nanook# ./kcov 
mmap: No such device

The device exists (it was able to open the fd, evidently):

root at ribbensteg:/home/nanook# ls -al /sys/kernel/debug/kcov 
-rw------- 1 root root 0 Jan  1  1970 /sys/kernel/debug/kcov

Strace show me:

openat(AT_FDCWD, "/sys/kernel/debug/kcov", O_RDWR) = 3
ioctl(3, CHIOMOVE or CM_IOCGATR, 0x10000) = 0
mmap(NULL, 524288, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = -1 ENODEV (No such device)

It doesn't look like the error paths in kcov_mmap are hitting.

Any ideas?

Thanks,
Mark.

  reply	other threads:[~2016-06-15 11:45 UTC|newest]

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-06-14 16:57 [PATCH v2] arm64: allow building with kcov coverage on ARM64 Alexander Potapenko
2016-06-14 16:57 ` Alexander Potapenko
2016-06-14 17:16 ` Alexander Potapenko
2016-06-14 17:16   ` Alexander Potapenko
2016-06-14 17:55 ` Mark Rutland
2016-06-14 17:55   ` Mark Rutland
2016-06-14 18:16   ` Alexander Potapenko
2016-06-14 18:16     ` Alexander Potapenko
2016-06-15  9:25     ` Mark Rutland
2016-06-15  9:25       ` Mark Rutland
2016-06-15 11:44       ` Mark Rutland [this message]
2016-06-15 11:44         ` Mark Rutland
2016-06-15 11:53         ` Alexander Potapenko
2016-06-15 11:53           ` Alexander Potapenko
2016-06-15 14:25           ` Mark Rutland
2016-06-15 14:25             ` Mark Rutland
2016-06-15 14:36             ` Dmitry Vyukov
2016-06-15 14:36               ` Dmitry Vyukov
2016-06-15 15:05               ` Mark Rutland
2016-06-15 15:05                 ` Mark Rutland
2016-06-15 15:16                 ` Dmitry Vyukov
2016-06-15 15:16                   ` Dmitry Vyukov
2016-06-16 10:47             ` James Morse
2016-06-16 10:47               ` James Morse
2016-06-16 15:20               ` Alexander Potapenko
2016-06-16 15:20                 ` Alexander Potapenko
2016-06-16 15:44                 ` Mark Rutland
2016-06-16 15:44                   ` Mark Rutland
2016-06-16 16:25                   ` Catalin Marinas
2016-06-16 16:25                     ` Catalin Marinas
2016-06-16 16:32                     ` Mark Rutland
2016-06-16 16:32                       ` Mark Rutland
2016-06-16 16:36                       ` Alexander Potapenko
2016-06-16 16:36                         ` Alexander Potapenko
2016-06-16 16:36                         ` James Morse
2016-06-16 16:36                           ` James Morse
2016-06-16 16:39                       ` Catalin Marinas
2016-06-16 16:39                         ` Catalin Marinas

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20160615114438.GC3984@leverpostej \
    --to=mark.rutland@arm.com \
    --cc=akpm@linux-foundation.org \
    --cc=ard.biesheuvel@linaro.org \
    --cc=catalin.marinas@arm.com \
    --cc=christoffer.dall@linaro.org \
    --cc=dvyukov@google.com \
    --cc=glider@google.com \
    --cc=kcc@google.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=marc.zyngier@arm.com \
    --cc=quentin.casasnovas@oracle.com \
    --cc=syzkaller@googlegroups.com \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.