[Crash-utility] Re: [PATCH v2 3/3] Enable resolving mangled Rust symbol in lockless ring buffer
On Tue, Sep 30, 2025 at 8:18 PM lijiang <lijiang(a)redhat.com> wrote:
On Tue, Sep 30, 2025 at 3:01 PM Mikhail Zaslonko <zaslonko(a)linux.ibm.com> wrote:
>
> Hello,
>
> On 9/30/2025 4:53 AM, lijiang wrote:
> > On Tue, Sep 30, 2025 at 2:18 AM Mikhail Zaslonko <zaslonko(a)linux.ibm.com>
> > wrote:
> >
> >> Hi Lianbo,
> >>
> >> It seems we have a problem printing disassembly blocks in the log after
> >> this patch (at least on s390).
> >> See number of empty lines printed below.
> >>
> >
> > Can you try it with the following two patches?
> > [1]
> > https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01621.html
> This patch is present on crash master, doesnt affect the issue.
> > [2]
> > https://www.mail-archive.com/devel@lists.crash-utility.osci.io/msg01636.html
> >
> This one helps indeed! At least I do not se the blanks lines in my scenario.
> BUT, if I use 'log -R' the blank lines are back again!
Thanks for the information, Mikhail.
Let me see how to debug this(although I can not reproduce it on s390x).
I didn't reproduce the issue on my s390x machine either, maybe sharing
the vmcore to us can help.
Thanks,
Tao Liu
Thanks
Lianbo
>
>
> >
> >> Before the patch:
> >> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> >> 0000000015800000 0000000000001000
> >> [ 21.408787] 0000000008e30000 00000000b0001000
> >> 0000000000000000 0000000000000a55
> >> [ 21.408790] 0000000004c52300 000002aa3780c000
> >> 00000000084281d0 0000038000bfbd28
> >> [ 21.408794] 00000000075e9500 0000000004c52300
> >> 0000038000bfbbf0 0000038000bfbb90
> >> [ 21.408860] Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> >> %r5,2952794112
> >> 000000000e0acf4e: ec4100b30659 risbgn
> >> %r4,%r1,0,179,6
> >> #000000000e0acf54: 0e24 mvcl
> >> %r2,%r4
> >> >000000000e0acf56: a7280000 lhi
> >> %r2,0
> >> 000000000e0acf5a: eb6ff0a80004 lmg
> >> %r6,%r15,168(%r15)
> >> 000000000e0acf60: b9140022 lgfr
> >> %r2,%r2
> >> 000000000e0acf64: 07fe bcr
> >> 15,%r14
> >> 000000000e0acf66: 47000700 bc
> >> 0,1792
> >> [ 21.408883] Call Trace:
> >>
> >> After the patch:
> >> [ 21.408784] Krnl GPRS: 000002aa3780c000 0000000000238c00
> >> 0000000015800000 0000000000001000
> >> [ 21.408787] 0000000008e30000 00000000b0001000
> >> 0000000000000000 0000000000000a55
> >> [ 21.408790] 0000000004c52300 000002aa3780c000
> >> 00000000084281d0 0000038000bfbd28
> >> [ 21.408794] 00000000075e9500 0000000004c52300
> >> 0000038000bfbbf0 0000038000bfbb90
> >> [ 21.408860]
> >>
> >>
> >>
> >>
> >>
> >>
> >> Krnl Code: 000000000e0acf48: c05fb0001000 llilf
> >> %r5,2952794112
> >> [ 21.408883] Call Trace:
> >>
> >> I think your approach of storing printable characters in the buffer with
> >> the intention to modify it
> >> afterwards (see [1] below) instead of writing it character wise does not
> >> work when the input data
> >> contains several lines. Those '\n' are written one by one, what
leads to
> >> the result shown above.
> >> You should probably buffer and 'demangle' each line separately.
> >>
> >
> > Looks like different issues. Can you share your vmcore and vmlinux with
> > me? I did not reproduce it.
>
>
> >
> > Thanks
> > Lianbo
> >
> >>
> >>
> >
>