Date: Sun, 18 Nov 2007 15:04:38 +0900 From: Pyun YongHyeon <pyunyh@gmail.com> To: Jack Vogel <jfvogel@gmail.com> Cc: Mike Silbersack <silby@freebsd.org>, Andre Oppermann <andre@freebsd.org>, Kip Macy <kip.macy@gmail.com>, Denis Shaposhnikov <dsh@vlink.ru>, freebsd-current@freebsd.org, Mike Andrews <mandrews@bit0.com> Subject: Re: bizarre em + TSO + MSS issue in RELENG_7 Message-ID: <20071118060438.GB1044@cdnetworks.co.kr> In-Reply-To: <2a41acea0711172200n160ff8f2rb2d0b81dfab236ea@mail.gmail.com> References: <b1fa29170711171308x62a6371dnbb939748c5c59ae2@mail.gmail.com> <20071117170537.F59492@mindcrime.int.bit0.com> <b1fa29170711171519r65473426s1b9f3d9666ff6a92@mail.gmail.com> <20071117182232.T59492@mindcrime.int.bit0.com> <b1fa29170711171619x24233a3cw4361e0f3ca395e4c@mail.gmail.com> <473F9552.50402@bit0.com> <b1fa29170711171804x36e4ae51ie03d01e4bc0220ac@mail.gmail.com> <473FBD1A.8010207@bit0.com> <20071118054409.GA1044@cdnetworks.co.kr> <2a41acea0711172200n160ff8f2rb2d0b81dfab236ea@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, Nov 17, 2007 at 10:00:16PM -0800, Jack Vogel wrote: [...] > > > > It seems that em_tso_setup() doesn't clear txd_upper/txd_lower in > > failure path so that unintialized value could be used in subsequent > > Tx descriptor setup. > > How about clearing those variable?(Patch attached) > > > > It seems that em(4) uses EM_TSO_SIZE(64K) to create DMA tag. A packet > > can have 64K payload under TSO so its the mximum size of the mbuf > > chain would be 64K + sizeof(link layer). So I guess the EM_TSO_SIZE > > should be increased to hold sizeof(link layer). > > It had been a long time since I looked into em(4) so I'm not sure. > > Huh? They are set to 0 on entry, and not touched again before you go > into the setup routine, your change has no effect. > Sorry for the noise. -- Regards, Pyun YongHyeon
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20071118060438.GB1044>