Re: [PATCH] ARM: hw_breakpoint: Handle inexact watchpoint addresses
From: Russell King - ARM Linux admin
Date: Thu Aug 06 2020 - 13:08:10 EST
On Thu, Aug 06, 2020 at 08:05:10AM -0700, Doug Anderson wrote:
> On Mon, Dec 2, 2019 at 8:36 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
> > Hi,
> > On Wed, Nov 20, 2019 at 11:18 AM Will Deacon <will@xxxxxxxxxx> wrote:
> > >
> > > On Sat, Oct 19, 2019 at 11:12:26AM -0700, Douglas Anderson wrote:
> > > > This is commit fdfeff0f9e3d ("arm64: hw_breakpoint: Handle inexact
> > > > watchpoint addresses") but ported to arm32, which has the same
> > > > problem.
> > > >
> > > > This problem was found by Android CTS tests, notably the
> > > > "watchpoint_imprecise" test . I tested locally against a copycat
> > > > (simplified) version of the test though.
> > > >
> > > >  https://android.googlesource.com/platform/bionic/+/master/tests/sys_ptrace_test.cpp
> > > >
> > > > Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
> > > > ---
> > > >
> > > > arch/arm/kernel/hw_breakpoint.c | 96 ++++++++++++++++++++++++---------
> > > > 1 file changed, 70 insertions(+), 26 deletions(-)
> > >
> > > Sorry for taking so long to look at this. After wrapping my head around the
> > > logic again
> > Yeah. It was a little weird and (unfortunately) arbitrarily different
> > in some places compared to the arm64 code.
> > > I think it looks fine, so please put it into the patch system
> > > with my Ack:
> > >
> > > Acked-by: Will Deacon <will@xxxxxxxxxx>
> > Thanks! Submitted as:
> > https://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=8944/1
> Oddly, I found that if I go visit that page now I see:
> > - - - Note 2 submitted by Russell King on 17 Jan 2020 11:16:34 (UTC) - - -
> > Moved to applied
> > Applied to git-curr (misc branch).
> Yet if I go check mainline the patch is not there. This came to my
> attention since we had my patch picked to the Chrome OS 4.19 tree and
> suddenly recently got a stable merge conflict with "ARM: 8986/1:
> hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints".
> Anyone know what happened here?
Yes. Stephen Rothwell raised a complaint against it, which you were
> Hi all,
> 116375be0461 ("ARM: 8944/1: hw_breakpoint: Handle inexact watchpoint addresses")
> is missing a Signed-off-by from its author.
My reply to Stephen's email was:
> Thanks Stephen, patch dropped.
> It looks like Doug used his "m.disordat.com" address to submit the
> patch through the web interface, and there was no From: in the patch
> itself, so that was used as the patch author. However, as you spotted,
> it was signed off using Doug's "chromium.org" address.
> I think it's time to make the patch system a bit more strict, checking
> that the submission address is mentioned in a signed-off-by tag
> somewhere in the commit message.
> Doug, the patch system does have your "chromium.org" address, if that's
> the one you want to use as the author, please submit using that instead.
Neither email got a response from you, so the patch was dropped and
nothing further happened.
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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