Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, Oct 24, 2011 at 6:12 AM, Ben Hutchings b...@decadent.org.uk wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. This indeed seems like a good idea to advocate getting things upstream (not just staging) but what about the case where we have upstream drivers from future kernels backported to older kernels and the newer driver is simply provided as a feature for users who may need new features / chipset support on their old distribution kernel? It seems this taint flag will be used for driers backported through compat-wireless, the compat kernel module or any other backported driver, even if it is indeed upstream and whereby kernel developer *do* commit to actually fixing issues. In our experience compat-wireless bugs *are real bugs*, not backport bugs so we do look into them. In our latest linux-next.git based release for example backport code consists only of 1.3804% of the code. Luis -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAB=ne6vt91thcbj7sjhjucadzzpqox+omcqjsej54vqatby...@mail.gmail.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, Dec 12, 2011 at 01:40:44PM -0800, Luis R. Rodriguez wrote: On Mon, Oct 24, 2011 at 6:12 AM, Ben Hutchings b...@decadent.org.uk wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. This indeed seems like a good idea to advocate getting things upstream (not just staging) but what about the case where we have upstream drivers from future kernels backported to older kernels and the newer driver is simply provided as a feature for users who may need new features / chipset support on their old distribution kernel? They continue to work without any loss of functionality. (After the follow-up patches to keep dynamic debugging and lock debugging working.) It seems this taint flag will be used for driers backported through compat-wireless, the compat kernel module or any other backported driver, even if it is indeed upstream and whereby kernel developer *do* commit to actually fixing issues. In our experience compat-wireless bugs *are real bugs*, not backport bugs so we do look into them. In our latest linux-next.git based release for example backport code consists only of 1.3804% of the code. Now you can look for (O) after the module name in a BUG/Oops message and you can tell whether the user really had the original or compat-wireless version of the driver. It is really up to each distributor or developer how they treat bug reports with the O taint. When handling Debian bug reports I won't automatically reject such a tainted kernel but I will look carefully at the module list. Ben. -- Ben Hutchings We get into the habit of living before acquiring the habit of thinking. - Albert Camus -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111212215818.gp3...@decadent.org.uk
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, Dec 12, 2011 at 1:58 PM, Ben Hutchings b...@decadent.org.uk wrote: On Mon, Dec 12, 2011 at 01:40:44PM -0800, Luis R. Rodriguez wrote: On Mon, Oct 24, 2011 at 6:12 AM, Ben Hutchings b...@decadent.org.uk wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. This indeed seems like a good idea to advocate getting things upstream (not just staging) but what about the case where we have upstream drivers from future kernels backported to older kernels and the newer driver is simply provided as a feature for users who may need new features / chipset support on their old distribution kernel? They continue to work without any loss of functionality. (After the follow-up patches to keep dynamic debugging and lock debugging working.) Great! It seems this taint flag will be used for driers backported through compat-wireless, the compat kernel module or any other backported driver, even if it is indeed upstream and whereby kernel developer *do* commit to actually fixing issues. In our experience compat-wireless bugs *are real bugs*, not backport bugs so we do look into them. In our latest linux-next.git based release for example backport code consists only of 1.3804% of the code. Now you can look for (O) after the module name in a BUG/Oops message and you can tell whether the user really had the original or compat-wireless version of the driver. It is really up to each distributor or developer how they treat bug reports with the O taint. When handling Debian bug reports I won't automatically reject such a tainted kernel but I will look carefully at the module list. I'm working on getting my companies to abandon 802.11 proprietary drivers for good. For Station mode of operation this is pretty much mission complete. For AP products.. this is work in progress. The out of tree flag is a good utility one can use to help justify working upstream but if we treat any future-kernel-backported-driver equally to any out of tree crap piece of shit driver, it seems to do unjustice to the value of a properly upstream backported driver. I will note that I put a lot of effort to ensure that the backport effort is upstream-centric in an *extremely* upstream-biased way, see how I label extra patches for tarballs [1]. If your patches are not upstream the only way you get into these tarballs are by providing patches into these directories: * pending-stable/ stable fixes from linux-next.git not yet on a stable release * linux-next-cherry-picks/ patches upstream but that won't go to the stable release that we want to cherry pick * linux-next-pending/ patches posted on the public development mailing list, patch not yet merged due to the maintainer being away on vacation or whatever * crap/ patches not even posted publicly yet Each tarball used also gets pegged with a letter if *any* patch from any of these directories gets applied. The compat module, upon being loaded, will also print the kernel ring buffer the exact release, whether extra patches were provided, the upstream git tree used as base and so on. So -- although from a technical perspective this may mean Debian / other kernel developers may ignore the taint flag for compat-wireless it'd sure be nice to avoid it for them all together. Just can't think of a way to do it yet... If you agree should we continue to think of a way if its possible? [1] http://wireless.kernel.org/en/users/Download/stable#Legend Luis -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAB=NE6Wb9ySk6a1gB-edyF_uRe=-esehunbua+n0g2wygjx...@mail.gmail.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, Dec 12, 2011 at 2:47 PM, Luis R. Rodriguez mcg...@frijolero.org wrote: On Mon, Dec 12, 2011 at 1:58 PM, Ben Hutchings b...@decadent.org.uk wrote: On Mon, Dec 12, 2011 at 01:40:44PM -0800, Luis R. Rodriguez wrote: On Mon, Oct 24, 2011 at 6:12 AM, Ben Hutchings b...@decadent.org.uk wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. This indeed seems like a good idea to advocate getting things upstream (not just staging) but what about the case where we have upstream drivers from future kernels backported to older kernels and the newer driver is simply provided as a feature for users who may need new features / chipset support on their old distribution kernel? They continue to work without any loss of functionality. (After the follow-up patches to keep dynamic debugging and lock debugging working.) Great! It seems this taint flag will be used for driers backported through compat-wireless, the compat kernel module or any other backported driver, even if it is indeed upstream and whereby kernel developer *do* commit to actually fixing issues. In our experience compat-wireless bugs *are real bugs*, not backport bugs so we do look into them. In our latest linux-next.git based release for example backport code consists only of 1.3804% of the code. Now you can look for (O) after the module name in a BUG/Oops message and you can tell whether the user really had the original or compat-wireless version of the driver. It is really up to each distributor or developer how they treat bug reports with the O taint. When handling Debian bug reports I won't automatically reject such a tainted kernel but I will look carefully at the module list. I'm working on getting my companies to abandon 802.11 proprietary drivers for good. For Station mode of operation this is pretty much mission complete. For AP products.. this is work in progress. The out of tree flag is a good utility one can use to help justify working upstream but if we treat any future-kernel-backported-driver equally to any out of tree crap piece of shit driver, it seems to do unjustice to the value of a properly upstream backported driver. I will note that I put a lot of effort to ensure that the backport effort is upstream-centric in an *extremely* upstream-biased way, see how I label extra patches for tarballs [1]. If your patches are not upstream the only way you get into these tarballs are by providing patches into these directories: * pending-stable/ stable fixes from linux-next.git not yet on a stable release * linux-next-cherry-picks/ patches upstream but that won't go to the stable release that we want to cherry pick * linux-next-pending/ patches posted on the public development mailing list, patch not yet merged due to the maintainer being away on vacation or whatever * crap/ patches not even posted publicly yet Each tarball used also gets pegged with a letter if *any* patch from any of these directories gets applied. The compat module, upon being loaded, will also print the kernel ring buffer the exact release, whether extra patches were provided, the upstream git tree used as base and so on. So -- although from a technical perspective this may mean Debian / other kernel developers may ignore the taint flag for compat-wireless it'd sure be nice to avoid it for them all together. Just can't think of a way to do it yet... If you agree should we continue to think of a way if its possible? [1] http://wireless.kernel.org/en/users/Download/stable#Legend How about a way to peg a driver as a backport from future kernels? Like maybe MODULE_COMPAT() ? Luis -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/CAB=ne6w_ap2rylad4xylm8wmiuxrzbqzhczpeksvmsdq9...@mail.gmail.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, 2011-12-12 at 14:47 -0800, Luis R. Rodriguez wrote: On Mon, Dec 12, 2011 at 1:58 PM, Ben Hutchings b...@decadent.org.uk wrote: On Mon, Dec 12, 2011 at 01:40:44PM -0800, Luis R. Rodriguez wrote: [...] It seems this taint flag will be used for driers backported through compat-wireless, the compat kernel module or any other backported driver, even if it is indeed upstream and whereby kernel developer *do* commit to actually fixing issues. In our experience compat-wireless bugs *are real bugs*, not backport bugs so we do look into them. In our latest linux-next.git based release for example backport code consists only of 1.3804% of the code. Now you can look for (O) after the module name in a BUG/Oops message and you can tell whether the user really had the original or compat-wireless version of the driver. It is really up to each distributor or developer how they treat bug reports with the O taint. When handling Debian bug reports I won't automatically reject such a tainted kernel but I will look carefully at the module list. I'm working on getting my companies to abandon 802.11 proprietary drivers for good. For Station mode of operation this is pretty much mission complete. For AP products.. this is work in progress. The out of tree flag is a good utility one can use to help justify working upstream but if we treat any future-kernel-backported-driver equally to any out of tree crap piece of shit driver, it seems to do unjustice to the value of a properly upstream backported driver. Well, it's a warning that not all the kernel code comes from the original source tree that the version string identifies. It's not a value judgement (unlike TAINT_CRAP). I will note that I put a lot of effort to ensure that the backport effort is upstream-centric in an *extremely* upstream-biased way, see how I label extra patches for tarballs [1]. If your patches are not upstream the only way you get into these tarballs are by providing patches into these directories: * pending-stable/ stable fixes from linux-next.git not yet on a stable release * linux-next-cherry-picks/ patches upstream but that won't go to the stable release that we want to cherry pick * linux-next-pending/ patches posted on the public development mailing list, patch not yet merged due to the maintainer being away on vacation or whatever * crap/ patches not even posted publicly yet Each tarball used also gets pegged with a letter if *any* patch from any of these directories gets applied. The compat module, upon being loaded, will also print the kernel ring buffer the exact release, whether extra patches were provided, the upstream git tree used as base and so on. Thanks, I appreciate that. So -- although from a technical perspective this may mean Debian / other kernel developers may ignore the taint flag for compat-wireless it'd sure be nice to avoid it for them all together. Just can't think of a way to do it yet... If you agree should we continue to think of a way if its possible? Maybe we should be talking about updating the distribution packages instead. For the Debian kernel packages, we backport various drivers to the stable distribution to add support for new hardware. Please mail debian-kernel@lists.debian.org if you would like to work with us on that. Ben. [1] http://wireless.kernel.org/en/users/Download/stable#Legend Luis -- Ben Hutchings Computers are not intelligent. They only think they are. signature.asc Description: This is a digitally signed message part
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Wed, 26 Oct 2011 21:55:28 -0400, Dave Jones da...@redhat.com wrote: On Thu, Oct 27, 2011 at 11:41:37AM +1030, Rusty Russell wrote: I think we need a taint_string() function, and instead of lockdep disabling itself it should note the taint string in its reports. Similarly for anything else (oops already does this). you mean like print_tainted() ? Wow, there's one terribly named function! So, yeah, kinda like that. Only remove the suckage. Thanks, Rusty. -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/87zkgiosm5@rustcorp.com.au
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Thu, Oct 27, 2011 at 11:41:37AM +1030, Rusty Russell wrote: On Wed, 26 Oct 2011 09:08:34 -0400, Nick Bowler nbow...@elliptictech.com wrote: On 2011-10-25 22:54 +0200, Greg KH wrote: On Tue, Oct 25, 2011 at 04:17:24PM -0400, Dave Jones wrote: On Tue, Oct 25, 2011 at 10:04:55PM +0200, Greg Kroah-Hartman wrote: On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. I'm assuming you mean this patch ? commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules Hm, this is the patch I was thinking about yes. But as you point out: [...] Perhaps the lockdep thing is totally different. I don't know about that check. Lockdep is disabled (for the whole system) by add_taint itself. The relevant commit that fixes TAINT_CRAP appears to be this one (circa 2.6.30): commit 574bbe782057fdf0490dc7dec906a2dc26363e20 Author: Frederic Weisbecker fweis...@gmail.com Date: Sat Apr 11 03:17:18 2009 +0200 lockdep: continue lock debugging despite some taints I didn't know about the dynamic debug problem. Is there more breakage that we haven't found yet? Remind me why we're trying to cripple out of tree module users? Gah, people are overloading taint. It doesn't mean don't do stuff, it means note the taint when something goes wrong. I agree, we shouldn't be changing logic in the kernel due to tainting, so removing any such checks would be a good idea. thanks, greg k-h -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111027054920.ga1...@kroah.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
* Rusty Russell (ru...@rustcorp.com.au) wrote: On Tue, 25 Oct 2011 16:17:24 -0400, Dave Jones da...@redhat.com wrote: commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules ... Signed-off-by: Roland Vossen rvos...@broadcom.com Acked-by: Jason Baron jba...@redhat.com Signed-off-by: Greg Kroah-Hartman gre...@suse.de Greg, you know better. This is why we have maintainers: I can't track patches I don't see. Grrr... If we want to support out of tree modules with this, should we just nuke the whole check, or do we still want to prevent certain types of tainted kernels from using this stuff ? It goes back to the first implementation of kernel markers. IIRC, it was to prevent dynamic debug stuff from circumventing licensing, but testing for *any* taint seems overbroad. Mathieu? This check for tainted modules was first introduced with markers, and then used by tracepoints, and then also by dynamic debug. The rationale for this check was mainly to ensure that the marker/tracepoint code would not trigger a crash when loading a module with incompatible module header, originally compiled for an older kernel, into a newer kernel. This problem would happen even if the said module does not contain any marker/tracepoint, because we happen to try to use fields that are non-existent in the module header. AFAIK, dynamic debug use a similar trick that require extra members in the module header, so checking that the module header format is compatible with the kernel would be enough. Is there a taint flag that allows us to check for this more narrowly ? TAINT_FORCED_MODULE would probably be the closest one we have now, although we might want to be more specific than that. Thanks, Mathieu Thanks, Rusty. PS. Can't see how this related to lockdep either... -- Mathieu Desnoyers Operating System Efficiency RD Consultant EfficiOS Inc. http://www.efficios.com -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111026061521.GB16408@Krystal
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On 2011-10-25 22:54 +0200, Greg KH wrote: On Tue, Oct 25, 2011 at 04:17:24PM -0400, Dave Jones wrote: On Tue, Oct 25, 2011 at 10:04:55PM +0200, Greg Kroah-Hartman wrote: On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. I'm assuming you mean this patch ? commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules Hm, this is the patch I was thinking about yes. But as you point out: [...] Perhaps the lockdep thing is totally different. I don't know about that check. Lockdep is disabled (for the whole system) by add_taint itself. The relevant commit that fixes TAINT_CRAP appears to be this one (circa 2.6.30): commit 574bbe782057fdf0490dc7dec906a2dc26363e20 Author: Frederic Weisbecker fweis...@gmail.com Date: Sat Apr 11 03:17:18 2009 +0200 lockdep: continue lock debugging despite some taints I didn't know about the dynamic debug problem. Is there more breakage that we haven't found yet? Remind me why we're trying to cripple out of tree module users? Cheers, -- Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/) -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111026130834.ga6...@elliptictech.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Wed, 26 Oct 2011 09:08:34 -0400, Nick Bowler nbow...@elliptictech.com wrote: On 2011-10-25 22:54 +0200, Greg KH wrote: On Tue, Oct 25, 2011 at 04:17:24PM -0400, Dave Jones wrote: On Tue, Oct 25, 2011 at 10:04:55PM +0200, Greg Kroah-Hartman wrote: On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. I'm assuming you mean this patch ? commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules Hm, this is the patch I was thinking about yes. But as you point out: [...] Perhaps the lockdep thing is totally different. I don't know about that check. Lockdep is disabled (for the whole system) by add_taint itself. The relevant commit that fixes TAINT_CRAP appears to be this one (circa 2.6.30): commit 574bbe782057fdf0490dc7dec906a2dc26363e20 Author: Frederic Weisbecker fweis...@gmail.com Date: Sat Apr 11 03:17:18 2009 +0200 lockdep: continue lock debugging despite some taints I didn't know about the dynamic debug problem. Is there more breakage that we haven't found yet? Remind me why we're trying to cripple out of tree module users? Gah, people are overloading taint. It doesn't mean don't do stuff, it means note the taint when something goes wrong. I think we need a taint_string() function, and instead of lockdep disabling itself it should note the taint string in its reports. Similarly for anything else (oops already does this). Dynamic debugging should just crash like anything else if they force a module load and get it wrong: it's the least of their problems. If noone hugely objects, I'll create a patch series... Thanks, Rusty. -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/874nyvnsqe@rustcorp.com.au
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Thu, Oct 27, 2011 at 11:41:37AM +1030, Rusty Russell wrote: I think we need a taint_string() function, and instead of lockdep disabling itself it should note the taint string in its reports. Similarly for anything else (oops already does this). you mean like print_tainted() ? Dave -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111027015528.ga19...@redhat.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, 2011-10-25 at 14:26 +1030, Rusty Russell wrote: On Mon, 24 Oct 2011 07:57:03 -0700, Randy Dunlap rdun...@xenotime.net wrote: On 10/24/11 06:12, Ben Hutchings wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. Ben. include/linux/kernel.h |1 + kernel/module.c|5 + kernel/panic.c |2 ++ scripts/mod/modpost.c |7 +++ 4 files changed, 15 insertions(+), 0 deletions(-) Hi, Please add 'O' to Documentation/oops-tracing.txt. Sorry, this is the second time I've missed that now... I did that, and applied the patch. See below. [...] Thanks to everyone. Ben. -- Ben Hutchings DNRC Motto: I can please only one person per day. Today is not your day. Tomorrow isn't looking good either. signature.asc Description: This is a digitally signed message part
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, 2011-10-25 at 11:38 -0400, Nick Bowler wrote: On 2011-10-25 14:26 +1030, Rusty Russell wrote: From: Ben Hutchings b...@decadent.org.uk Subject: module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree Date: Mon, 24 Oct 2011 15:12:28 +0200 Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk Reviewed-by: Dave Jones da...@redhat.com Acked-by: Greg Kroah-Hartman gre...@suse.de Signed-off-by: Rusty Russell ru...@rustcorp.com.au (patched oops-tracing.txt) --- Documentation/oops-tracing.txt |2 ++ include/linux/kernel.h |1 + kernel/module.c|5 + kernel/panic.c |2 ++ scripts/mod/modpost.c |7 +++ 5 files changed, 17 insertions(+) This patch prevents the use of lockdep for debugging out of tree modules, which is rather mean. It was already disabled for staging modules, which seems equally unhelpful. Maybe it should print taint flags at the top of its warnings instead. Ben. -- Ben Hutchings DNRC Motto: I can please only one person per day. Today is not your day. Tomorrow isn't looking good either. signature.asc Description: This is a digitally signed message part
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: On 2011-10-25 18:05 +0200, Ben Hutchings wrote: On Tue, 2011-10-25 at 11:38 -0400, Nick Bowler wrote: This patch prevents the use of lockdep for debugging out of tree modules, which is rather mean. It was already disabled for staging modules, which seems equally unhelpful. This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. greg k-h -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111025200455.ga6...@kroah.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, Oct 25, 2011 at 10:04:55PM +0200, Greg Kroah-Hartman wrote: On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: On 2011-10-25 18:05 +0200, Ben Hutchings wrote: On Tue, 2011-10-25 at 11:38 -0400, Nick Bowler wrote: This patch prevents the use of lockdep for debugging out of tree modules, which is rather mean. It was already disabled for staging modules, which seems equally unhelpful. This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. I'm assuming you mean this patch ? commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules Driver modules from the staging directory are marked 'tainted' by module.c. Subsequently, tainted modules are denied dynamic debugging. This is unwanted behavior, since staging modules should be able to use the dynamic debugging mechanism. Please merge this also into the staging-linus branch. Signed-off-by: Roland Vossen rvos...@broadcom.com Acked-by: Jason Baron jba...@redhat.com Signed-off-by: Greg Kroah-Hartman gre...@suse.de diff --git a/kernel/module.c b/kernel/module.c index d5938a5..4d5c16a 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2790,7 +2790,7 @@ static struct module *load_module(void __user *umod, } /* This has to be done once we're sure module name is unique. */ - if (!mod-taints) + if (!mod-taints || mod-taints == (1UTAINT_CRAP)) dynamic_debug_setup(info.debug, info.num_debug); /* Find duplicate symbols */ @@ -2827,7 +2827,7 @@ static struct module *load_module(void __user *umod, module_bug_cleanup(mod); ddebug: - if (!mod-taints) + if (!mod-taints || mod-taints == (1UTAINT_CRAP)) dynamic_debug_remove(info.debug); unlock: mutex_unlock(module_mutex); If we want to support out of tree modules with this, should we just nuke the whole check, or do we still want to prevent certain types of tainted kernels from using this stuff ? (sidenote: it's not immediately obvious to me that this is the right patch, as dynamic debug lockdep are separate things, though this was the only thing in kernel/module.c's history this year that sounds similar) Dave -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111025201723.ga25...@redhat.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, Oct 25, 2011 at 04:17:24PM -0400, Dave Jones wrote: On Tue, Oct 25, 2011 at 10:04:55PM +0200, Greg Kroah-Hartman wrote: On Tue, Oct 25, 2011 at 12:51:42PM -0400, Nick Bowler wrote: On 2011-10-25 18:05 +0200, Ben Hutchings wrote: On Tue, 2011-10-25 at 11:38 -0400, Nick Bowler wrote: This patch prevents the use of lockdep for debugging out of tree modules, which is rather mean. It was already disabled for staging modules, which seems equally unhelpful. This is not the case: lockdep works fine with staging modules. Yes, that was fixed a few kernel versions ago. Now you might want to update that fix for the TAINT_OOT_MODULE flag as well, if you feel it is needed. I'm assuming you mean this patch ? commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules Hm, this is the patch I was thinking about yes. But as you point out: If we want to support out of tree modules with this, should we just nuke the whole check, or do we still want to prevent certain types of tainted kernels from using this stuff ? I don't know, there was some reason we didn't want to run dynamic_debug for normal tainted kernel modules, but I can't recall it at the moment, sorry. (sidenote: it's not immediately obvious to me that this is the right patch, as dynamic debug lockdep are separate things, though this was the only thing in kernel/module.c's history this year that sounds similar) Perhaps the lockdep thing is totally different. I don't know about that check. thanks, greg k-h -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111025205410.ga7...@kroah.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Tue, 25 Oct 2011 16:17:24 -0400, Dave Jones da...@redhat.com wrote: commit 7816c45bf13255157c00fb8aca86cb64d825e878 Author: Roland Vossen rvos...@broadcom.com Date: Thu Apr 7 11:20:58 2011 +0200 modules: Enabled dynamic debugging for staging modules ... Signed-off-by: Roland Vossen rvos...@broadcom.com Acked-by: Jason Baron jba...@redhat.com Signed-off-by: Greg Kroah-Hartman gre...@suse.de Greg, you know better. This is why we have maintainers: I can't track patches I don't see. Grrr... If we want to support out of tree modules with this, should we just nuke the whole check, or do we still want to prevent certain types of tainted kernels from using this stuff ? It goes back to the first implementation of kernel markers. IIRC, it was to prevent dynamic debug stuff from circumventing licensing, but testing for *any* taint seems overbroad. Mathieu? Thanks, Rusty. PS. Can't see how this related to lockdep either... -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/87zkgoo09f@rustcorp.com.au
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, Oct 24, 2011 at 03:12:28PM +0200, Ben Hutchings wrote: Use of the GPL or a compatible licence doesn't necessarily make the code any good. We already consider staging modules to be suspect, and this should also be true for out-of-tree modules which may receive very little review. Signed-off-by: Ben Hutchings b...@decadent.org.uk --- Debian has been carrying this for the last few kernel versions. The recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest that this might be more generally useful. Looks good to me. Reviewed-by: Dave Jones da...@redhat.com -- To UNSUBSCRIBE, email to debian-kernel-requ...@lists.debian.org with a subject of unsubscribe. Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/20111024135847.ga26...@redhat.com
Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On 10/24/11 06:12, Ben Hutchings wrote:
Use of the GPL or a compatible licence doesn't necessarily make the code
any good. We already consider staging modules to be suspect, and this
should also be true for out-of-tree modules which may receive very
little review.
Signed-off-by: Ben Hutchings b...@decadent.org.uk
---
Debian has been carrying this for the last few kernel versions. The
recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest
that this might be more generally useful.
Ben.
include/linux/kernel.h |1 +
kernel/module.c|5 +
kernel/panic.c |2 ++
scripts/mod/modpost.c |7 +++
4 files changed, 15 insertions(+), 0 deletions(-)
Hi,
Please add 'O' to Documentation/oops-tracing.txt.
Thanks.
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 46ac9a5..2c05967 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -369,6 +369,7 @@ extern enum system_states {
#define TAINT_WARN 9
#define TAINT_CRAP 10
#define TAINT_FIRMWARE_WORKAROUND11
+#define TAINT_OOT_MODULE 12
extern const char hex_asc[];
#define hex_asc_lo(x)hex_asc[((x) 0x0f)]
diff --git a/kernel/module.c b/kernel/module.c
index 04379f92..c0872f1 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2487,6 +2487,9 @@ static int check_modinfo(struct module *mod, struct
load_info *info)
return -ENOEXEC;
}
+ if (!get_modinfo(info, intree))
+ add_taint_module(mod, TAINT_OOT_MODULE);
+
if (get_modinfo(info, staging)) {
add_taint_module(mod, TAINT_CRAP);
printk(KERN_WARNING %s: module is from the staging directory,
@@ -3257,6 +3260,8 @@ static char *module_flags(struct module *mod, char *buf)
buf[bx++] = '(';
if (mod-taints (1 TAINT_PROPRIETARY_MODULE))
buf[bx++] = 'P';
+ else if (mod-taints (1 TAINT_OOT_MODULE))
+ buf[bx++] = 'O';
if (mod-taints (1 TAINT_FORCED_MODULE))
buf[bx++] = 'F';
if (mod-taints (1 TAINT_CRAP))
diff --git a/kernel/panic.c b/kernel/panic.c
index d7bb697..b2659360 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -177,6 +177,7 @@ static const struct tnt tnts[] = {
{ TAINT_WARN, 'W', ' ' },
{ TAINT_CRAP, 'C', ' ' },
{ TAINT_FIRMWARE_WORKAROUND,'I', ' ' },
+ { TAINT_OOT_MODULE, 'O', ' ' },
};
/**
@@ -194,6 +195,7 @@ static const struct tnt tnts[] = {
* 'W' - Taint on warning.
* 'C' - modules from drivers/staging are loaded.
* 'I' - Working around severe firmware bug.
+ * 'O' - Out-of-tree module has been loaded.
*
* The string is overwritten by the next call to print_tainted().
*/
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index a509ff8..2bd594e 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1849,6 +1849,12 @@ static void add_header(struct buffer *b, struct module
*mod)
buf_printf(b, };\n);
}
+static void add_intree_flag(struct buffer *b, int is_intree)
+{
+ if (is_intree)
+ buf_printf(b, \nMODULE_INFO(intree, \Y\);\n);
+}
+
static void add_staging_flag(struct buffer *b, const char *name)
{
static const char *staging_dir = drivers/staging;
@@ -2169,6 +2175,7 @@ int main(int argc, char **argv)
buf.pos = 0;
add_header(buf, mod);
+ add_intree_flag(buf, !external_module);
add_staging_flag(buf, mod-name);
err |= add_versions(buf, mod);
add_depends(buf, mod, modules);
--
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***
--
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Re: [PATCH] module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
On Mon, 24 Oct 2011 07:57:03 -0700, Randy Dunlap rdun...@xenotime.net wrote:
On 10/24/11 06:12, Ben Hutchings wrote:
Use of the GPL or a compatible licence doesn't necessarily make the code
any good. We already consider staging modules to be suspect, and this
should also be true for out-of-tree modules which may receive very
little review.
Signed-off-by: Ben Hutchings b...@decadent.org.uk
---
Debian has been carrying this for the last few kernel versions. The
recent thread '[RFC] virtualbox tainting.' and discussions at KS suggest
that this might be more generally useful.
Ben.
include/linux/kernel.h |1 +
kernel/module.c|5 +
kernel/panic.c |2 ++
scripts/mod/modpost.c |7 +++
4 files changed, 15 insertions(+), 0 deletions(-)
Hi,
Please add 'O' to Documentation/oops-tracing.txt.
I did that, and applied the patch. See below.
Thanks,
Rusty.
From: Ben Hutchings b...@decadent.org.uk
Subject: module,bug: Add TAINT_OOT_MODULE flag for modules not built in-tree
Date: Mon, 24 Oct 2011 15:12:28 +0200
Use of the GPL or a compatible licence doesn't necessarily make the code
any good. We already consider staging modules to be suspect, and this
should also be true for out-of-tree modules which may receive very
little review.
Signed-off-by: Ben Hutchings b...@decadent.org.uk
Reviewed-by: Dave Jones da...@redhat.com
Acked-by: Greg Kroah-Hartman gre...@suse.de
Signed-off-by: Rusty Russell ru...@rustcorp.com.au (patched oops-tracing.txt)
---
Documentation/oops-tracing.txt |2 ++
include/linux/kernel.h |1 +
kernel/module.c|5 +
kernel/panic.c |2 ++
scripts/mod/modpost.c |7 +++
5 files changed, 17 insertions(+)
diff --git a/Documentation/oops-tracing.txt b/Documentation/oops-tracing.txt
--- a/Documentation/oops-tracing.txt
+++ b/Documentation/oops-tracing.txt
@@ -263,6 +263,8 @@ characters, each representing a particul
12: 'I' if the kernel is working around a severe bug in the platform
firmware (BIOS or similar).
+ 13: 'O' if an externally-built (out-of-tree) module has been loaded.
+
The primary reason for the 'Tainted: ' string is to tell kernel
debuggers if this is a clean kernel or if anything unusual has
occurred. Tainting is permanent: even if an offending module is
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -369,6 +369,7 @@ extern enum system_states {
#define TAINT_WARN 9
#define TAINT_CRAP 10
#define TAINT_FIRMWARE_WORKAROUND 11
+#define TAINT_OOT_MODULE 12
extern const char hex_asc[];
#define hex_asc_lo(x) hex_asc[((x) 0x0f)]
diff --git a/kernel/module.c b/kernel/module.c
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2487,6 +2487,9 @@ static int check_modinfo(struct module *
return -ENOEXEC;
}
+ if (!get_modinfo(info, intree))
+ add_taint_module(mod, TAINT_OOT_MODULE);
+
if (get_modinfo(info, staging)) {
add_taint_module(mod, TAINT_CRAP);
printk(KERN_WARNING %s: module is from the staging directory,
@@ -3257,6 +3260,8 @@ static char *module_flags(struct module
buf[bx++] = '(';
if (mod-taints (1 TAINT_PROPRIETARY_MODULE))
buf[bx++] = 'P';
+ else if (mod-taints (1 TAINT_OOT_MODULE))
+ buf[bx++] = 'O';
if (mod-taints (1 TAINT_FORCED_MODULE))
buf[bx++] = 'F';
if (mod-taints (1 TAINT_CRAP))
diff --git a/kernel/panic.c b/kernel/panic.c
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -177,6 +177,7 @@ static const struct tnt tnts[] = {
{ TAINT_WARN, 'W', ' ' },
{ TAINT_CRAP, 'C', ' ' },
{ TAINT_FIRMWARE_WORKAROUND,'I', ' ' },
+ { TAINT_OOT_MODULE, 'O', ' ' },
};
/**
@@ -194,6 +195,7 @@ static const struct tnt tnts[] = {
* 'W' - Taint on warning.
* 'C' - modules from drivers/staging are loaded.
* 'I' - Working around severe firmware bug.
+ * 'O' - Out-of-tree module has been loaded.
*
* The string is overwritten by the next call to print_tainted().
*/
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -1849,6 +1849,12 @@ static void add_header(struct buffer *b,
buf_printf(b, };\n);
}
+static void add_intree_flag(struct buffer *b, int is_intree)
+{
+ if (is_intree)
+ buf_printf(b, \nMODULE_INFO(intree, \Y\);\n);
+}
+
static void add_staging_flag(struct buffer *b, const char *name)
{
static const char *staging_dir = drivers/staging;
@@ -2169,6 +2175,7 @@ int main(int argc, char **argv)
buf.pos = 0;
