Hi, On Tuesday, December 27, 2016 11:41:12 AM David Miller wrote: > From: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> > Date: Tue, 27 Dec 2016 17:06:19 +0100 > > > On Tuesday, December 27, 2016 11:08:24 AM Bartlomiej Zolnierkiewicz wrote: > >> > >> Hi, > >> > >> On Monday, December 26, 2016 11:47:24 AM David Miller wrote: > >> > From: Luiz Carlos Ramos <lramos.prof@xxxxxxxxxxxx> > >> > Date: Tue, 11 Oct 2016 22:12:45 -0300 > >> > > >> > > This humble patch was sent one or two months before, and had no actions, > >> > > except for a colleague reply which friendly pointed out some formatting > >> > > problems (which were solved in a second message). > >> > > > >> > > It relates to an old code, the legacy IDE driver, but the bug it > >> > > addresses is real. The code, although rarely used, is > >> > > still there to be compiled if one chooses to do so (like me). > >> > > > >> > > Also, the fix has a very low risk of present collateral effects IMHO. > >> > > It is already compiled and tested in some embedded machines. > >> > > > >> > > So, again IMHO, it is worth be fixed. > >> > > > >> > > This email is a second trial with it. I hope it can help the one or two > >> > > guys out there which are still running the legacy IDE driver and > >> > > haven't noticed the former email. > >> > > > >> > > Best regards, > >> > > > >> > > Signed-off-by: Luiz Carlos Ramos <lramos.prof@xxxxxxxxxxxx> > >> > > >> > This bug was introduced by commit > >> > 20df429dd6671804999493baf2952f82582869fa ("ide-generic: handle probing > >> > of legacy io-ports v5") which seems poorly tested. > >> > >> Please always cc: the original commit author. > >> > >> > Applied and queued up for -stable, th anks. > >> > >> For some reason I've never got the discussed patch from > >> linux-ide ML though I now have found in the patchwork: > >> > >> https://patchwork.ozlabs.org/patch/680975/ > >> > >> The patch is incorrect. If you have PCI IDE devices (like in > >> the case described in the situation being "fixed" by the patch) > >> you should use the correct PCI IDE host driver for proper > >> operation and not ide-generic host driver (the latter still can > >> be used by using kernel parameters). > > > > Moreover this patch introduces a regression. In the situation > > when there are no PCI IDE devices and the probing should be done > > automatically (for the first two legacy IDE ports) it will be no > > longer done. > > > > Now back to the using correct PCI IDE host drivers - Luiz what > > are the systems that you need this patch on? Could you please > > get 'lspci -nn' command output from them? > > The original code before the patch in question probed the interfaces > unconditionally, probe_mask was a static int set to "0x03". > > Commit 20df429dd6671804999493baf2952f82582869fa changed the default > behavior, as well as adding a new module parameter whose behavior > makes no sense at all. Inverted bit logic? Give me a break. > > Sorry, no, the fix is correct and I'm pushing it to Linus. The "fix" is not correct and is not needed. 99% of users of ide-generic used it by mistake and should have used the designated host drivers for their hardware or PCI IDE generic host driver (not ide-generic one). Alan Cox did the work on fixing this for his pata_legacy libata host driver and later Borislav back-ported needed changes to ide-generic host driver in commit 20df429dd6671804999493baf2952f82582869fa (in *2008*). Also the "fix" is not a revert but a new patch which introduces a real regression described by me in the previous mail. Best regards, -- Bartlomiej Zolnierkiewicz Samsung R&D Institute Poland Samsung Electronics -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html