lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 8 Nov 2017 21:39:11 +0000 From: "Levin, Alexander (Sasha Levin)" <alexander.levin@....verizon.com> To: Mark Brown <broonie@...nel.org> CC: "Levin, Alexander (Sasha Levin)" <alexander.levin@....verizon.com>, "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, "stable@...r.kernel.org" <stable@...r.kernel.org>, Jiada Wang <jiada_wang@...tor.com> Subject: Re: [PATCH AUTOSEL for-4.9 04/53] spi: imx: adjust watermark level according to transfer length On Wed, Nov 08, 2017 at 08:57:52PM +0000, Mark Brown wrote: >On Wed, Nov 08, 2017 at 08:49:55PM +0000, Levin, Alexander (Sasha Levin) wrote: >> From: Jiada Wang <jiada_wang@...tor.com> >> >> [ Upstream commit 66459c5a50a787c474b734b586328f7111ab6df0 ] >> >> Previously DMA watermark level is configured to fifosize/2, >> DMA mode can be used only when transfer length can be divided >> by 'watermark level * bpw', which makes DMA mode not pratical. >> >> This patch adjusts watermark level to largest number (no bigger >> than fifosize/2) which can divide 'tranfer length / bpw' for >> each transfer. > >This seems like an optimization not a bug fix... Hm, is it? I read it as "DMA is not being used at all even though we thought we're using it". Yes, the impact is "just" performance, but doesn't it result in quite a significat impact? -- Thanks, Sasha
Powered by blists - more mailing lists