Re: [PATCH v4 RESEND net-next] net: socket: use BIT() for MSG_*

From: Guenter Roeck
Date: Tue Mar 16 2021 - 19:56:28 EST


On 3/16/21 4:02 PM, Andy Shevchenko wrote:
>
>
> On Wednesday, March 17, 2021, Guenter Roeck <linux@xxxxxxxxxxxx <mailto:linux@xxxxxxxxxxxx>> wrote:
>
> Hi,
>
> On Tue, Mar 09, 2021 at 05:51:35PM -0800, menglong8.dong@xxxxxxxxx <mailto:menglong8.dong@xxxxxxxxx> wrote:
> > From: Menglong Dong <dong.menglong@xxxxxxxxxx <mailto:dong.menglong@xxxxxxxxxx>>
> >
> > The bit mask for MSG_* seems a little confused here. Replace it
> > with BIT() to make it clear to understand.
> >
> > Signed-off-by: Menglong Dong <dong.menglong@xxxxxxxxxx <mailto:dong.menglong@xxxxxxxxxx>>
>
> I must admit that I am a bit puzzled,
>
>
> I have checked the values and don’t see a problem. So, the only difference is the type int vs. unsigned long. I think this simply reveals an issue somewhere in the code.
>  

I am currently trying to "bisect" the individual bits. We'll see if I can find
the culprit(s).

Guenter

>
>
>  but with this patch in the tree
> (in next-20210316) several of my qemu network interface tests fail
> to get an IP address. So far I have only seen this with mips64
> tests, but that may be because I only started running those tests
> on various architectures.
>
> The tests do nothing special: With CONFIG_IP_PNP_DHCP=n, run udhcpc
> in qemu to get an IP address. With this patch in place, udhcpc fails.
> With this patch reverted, udhcpc gets the IP address as expected.
> The error reported by udhcpc is:
>
> udhcpc: sending discover
> udhcpc: read error: Invalid argument, reopening socket
>
> Reverting this patch fixes the problem.
>
> Guenter
>
> ---
> bisect log:
>
> # bad: [0f4b0bb396f6f424a7b074d00cb71f5966edcb8a] Add linux-next specific files for 20210316
> # good: [1e28eed17697bcf343c6743f0028cc3b5dd88bf0] Linux 5.12-rc3
> git bisect start 'HEAD' 'v5.12-rc3'
> # bad: [edd84c42baeffe66740143a04f24588fded94241] Merge remote-tracking branch 'drm-misc/for-linux-next'
> git bisect bad edd84c42baeffe66740143a04f24588fded94241
> # good: [a76f62d56da82bee1a4c35dd6375a8fdd57eca4e] Merge remote-tracking branch 'cel/for-next'
> git bisect good a76f62d56da82bee1a4c35dd6375a8fdd57eca4e
> # good: [e2924c67bae0cc15ca64dbe1ed791c96eed6d149] Merge remote-tracking branch 'rdma/for-next'
> git bisect good e2924c67bae0cc15ca64dbe1ed791c96eed6d149
> # bad: [a8f9952d218d816ff1a13c9385edd821a8da527d] selftests: fib_nexthops: List each test case in a different line
> git bisect bad a8f9952d218d816ff1a13c9385edd821a8da527d
> # bad: [4734a750f4674631ab9896189810b57700597aa7] mlxsw: Adjust some MFDE fields shift and size to fw implementation
> git bisect bad 4734a750f4674631ab9896189810b57700597aa7
> # good: [32e76b187a90de5809d68c2ef3e3964176dacaf0] bpf: Document BPF_PROG_ATTACH syscall command
> git bisect good 32e76b187a90de5809d68c2ef3e3964176dacaf0
> # good: [ee75aef23afe6e88497151c127c13ed69f41aaa2] bpf, xdp: Restructure redirect actions
> git bisect good ee75aef23afe6e88497151c127c13ed69f41aaa2
> # bad: [90d181ca488f466904ea59dd5c836f766b69c71b] net: rose: Fix fall-through warnings for Clang
> git bisect bad 90d181ca488f466904ea59dd5c836f766b69c71b
> # bad: [537a0c5c4218329990dc8973068f3bfe5c882623] net: fddi: skfp: smt: Replace one-element array with flexible-array member
> git bisect bad 537a0c5c4218329990dc8973068f3bfe5c882623
> # bad: [97c2c69e1926260c78c7f1c0b2c987934f1dc7a1] virtio-net: support XDP when not more queues
> git bisect bad 97c2c69e1926260c78c7f1c0b2c987934f1dc7a1
> # good: [c1acda9807e2bbe1d2026b44f37d959d6d8266c8] Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next <http://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next>
> git bisect good c1acda9807e2bbe1d2026b44f37d959d6d8266c8
> # bad: [0bb3262c0248d44aea3be31076f44beb82a7b120] net: socket: use BIT() for MSG_*
> git bisect bad 0bb3262c0248d44aea3be31076f44beb82a7b120
> # first bad commit: [0bb3262c0248d44aea3be31076f44beb82a7b120] net: socket: use BIT() for MSG_*
>
>
>
> --
> With Best Regards,
> Andy Shevchenko
>
>