From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Neukum Subject: Re: inconsistent lock state with usbnet/asix usb ethernet and xhci Date: Tue, 27 Feb 2018 17:07:55 +0100 Message-ID: <1519747675.2649.3.camel@suse.com> References: <1519740421.7296.6.camel@gmail.com> <1519744167.7296.8.camel@gmail.com> <1519744400.7296.10.camel@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1519744400.7296.10.camel@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Eric Dumazet , Marek Szyprowski , LKML , 'Linux Samsung SOC' , Linux USB Mailing List , netdev@vger.kernel.org Cc: Dean Jenkins List-Id: linux-samsung-soc@vger.kernel.org Am Dienstag, den 27.02.2018, 07:13 -0800 schrieb Eric Dumazet: > On Tue, 2018-02-27 at 07:09 -0800, Eric Dumazet wrote: > > > > > > Note that for this one, it seems we also could perform stats updates in > > BH context, since skb is queued via defer_bh() > > > > But simplicity wins I guess. > > Thinking more about this, I am not sure we have any guarantee that TX > and RX can not run on multiple cpus. > > Using an unique syncp is not going to be safe, even if we make lockdep > happy enough with the local_irq save/restore. Unfortunately you are right. It is not guaranteed for some hardware. Regards Oliver From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: inconsistent lock state with usbnet/asix usb ethernet and xhci From: Oliver Neukum Message-Id: <1519747675.2649.3.camel@suse.com> Date: Tue, 27 Feb 2018 17:07:55 +0100 To: Eric Dumazet , Marek Szyprowski , LKML , 'Linux Samsung SOC' , Linux USB Mailing List , netdev@vger.kernel.org Cc: Dean Jenkins List-ID: QW0gRGllbnN0YWcsIGRlbiAyNy4wMi4yMDE4LCAwNzoxMyAtMDgwMCBzY2hyaWViIEVyaWMgRHVt YXpldDoKPiBPbiBUdWUsIDIwMTgtMDItMjcgYXQgMDc6MDkgLTA4MDAsIEVyaWMgRHVtYXpldCB3 cm90ZToKPiA+IAo+ID4gCj4gPiBOb3RlIHRoYXQgZm9yIHRoaXMgb25lLCBpdCBzZWVtcyB3ZSBh bHNvIGNvdWxkIHBlcmZvcm0gc3RhdHMgdXBkYXRlcyBpbgo+ID4gQkggY29udGV4dCwgc2luY2Ug c2tiIGlzIHF1ZXVlZCB2aWEgZGVmZXJfYmgoKQo+ID4gCj4gPiBCdXQgc2ltcGxpY2l0eSB3aW5z IEkgZ3Vlc3MuCj4gCj4gVGhpbmtpbmcgbW9yZSBhYm91dCB0aGlzLCBJIGFtIG5vdCBzdXJlIHdl IGhhdmUgYW55IGd1YXJhbnRlZSB0aGF0IFRYCj4gYW5kIFJYIGNhbiBub3QgcnVuIG9uIG11bHRp cGxlIGNwdXMuCj4gCj4gVXNpbmcgYW4gdW5pcXVlIHN5bmNwIGlzIG5vdCBnb2luZyB0byBiZSBz YWZlLCBldmVuIGlmIHdlIG1ha2UgbG9ja2RlcAo+IGhhcHB5IGVub3VnaCB3aXRoIHRoZSBsb2Nh bF9pcnEgc2F2ZS9yZXN0b3JlLgoKVW5mb3J0dW5hdGVseSB5b3UgYXJlIHJpZ2h0LiBJdCBpcyBu b3QgZ3VhcmFudGVlZCBmb3Igc29tZSBoYXJkd2FyZS4KCglSZWdhcmRzCgkJT2xpdmVyCi0tLQpU byB1bnN1YnNjcmliZSBmcm9tIHRoaXMgbGlzdDogc2VuZCB0aGUgbGluZSAidW5zdWJzY3JpYmUg bGludXgtdXNiIiBpbgp0aGUgYm9keSBvZiBhIG1lc3NhZ2UgdG8gbWFqb3Jkb21vQHZnZXIua2Vy bmVsLm9yZwpNb3JlIG1ham9yZG9tbyBpbmZvIGF0ICBodHRwOi8vdmdlci5rZXJuZWwub3JnL21h am9yZG9tby1pbmZvLmh0bWwK