On Thu, Jun 01, 2023 at 09:26:30AM -0400, Luiz Capitulino wrote: > > > On 2023-06-01 09:20, Greg KH wrote: > > > > > > > > > On Thu, Jun 01, 2023 at 09:13:21AM -0400, Luiz Capitulino wrote: > > > > > > > > > On 2023-06-01 02:06, Greg KH wrote: > > > > > > > > > > > > > > > > > > > On Wed, May 31, 2023 at 10:12:40PM -0400, Luiz Capitulino wrote: > > > > > Hi Paul, > > > > > > > > > > A number of stable kernels recently backported this upstream commit: > > > > > > > > > > """ > > > > > commit 4ce1f694eb5d8ca607fed8542d32a33b4f1217a5 > > > > > Author: Paul Moore <paul@xxxxxxxxxxxxxx> > > > > > Date: Wed Apr 12 13:29:11 2023 -0400 > > > > > > > > > > selinux: ensure av_permissions.h is built when needed > > > > > """ > > > > > > > > > > We're seeing a build issue with this commit where the "crash" tool will fail > > > > > to start, it complains that the vmlinux image and /proc/version don't match. > > > > > > > > > > A minimum reproducer would be having "make" version before 4.3 and building > > > > > the kernel with: > > > > > > > > > > $ make bzImages > > > > > $ make modules > > > > > > > > > > Then compare the version strings in the bzImage and vmlinux images, > > > > > we can use "strings" for this. For example, in the 5.10.181 kernel I get: > > > > > > > > > > $ strings vmlinux | egrep '^Linux version' > > > > > Linux version 5.10.181 (ec2-user@ip-172-31-79-134.ec2.internal) (gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-15), GNU ld version 2.29.1-31.amzn2) #2 SMP Thu Jun 1 01:26:38 UTC 2023 > > > > > > > > > > $ strings ./arch/x86_64/boot/bzImage | egrep 'ld version' > > > > > 5.10.181 (ec2-user@ip-172-31-79-134.ec2.internal) (gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-15), GNU ld version 2.29.1-31.amzn2) #1 SMP Thu Jun 1 01:23:59 UTC 2023 > > > > > > > > > > The version string in the bzImage doesn't have the "Linux version" part, but > > > > > I think this is added by the kernel when printing. If you compare the strings, > > > > > you'll see that they have a different build date and the "#1" and "#2" are > > > > > different. > > > > > > > > > > This only happens with commit 4ce1f694eb5 applied and older "make", in my case I > > > > > have "make" version 3.82. > > > > > > > > > > If I revert 4ce1f694eb5 or use "make" version 4.3 I get identical strings (except > > > > > for the "Linux version" part): > > > > > > > > > > $ strings vmlinux | egrep '^Linux version' > > > > > Linux version 5.10.181+ (ec2-user@ip-172-31-79-134.ec2.internal) (gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-15), GNU ld version 2.29.1-31.amzn2) #1 SMP Thu Jun 1 01:29:11 UTC 2023 > > > > > > > > > > $ strings ./arch/x86_64/boot/bzImage | egrep 'ld version' > > > > > 5.10.181+ (ec2-user@ip-172-31-79-134.ec2.internal) (gcc (GCC) 7.3.1 20180712 (Red Hat 7.3.1-15), GNU ld version 2.29.1-31.amzn2) #1 SMP Thu Jun 1 01:29:11 UTC 2023 > > > > > > > > > > Maybe the grouped target usage in 4ce1f694eb5 with older "make" is causing a > > > > > rebuild of the vmlinux image in "make modules"? If yes, is this expected? > > > > > > > > > > I'm afraid this issue could be high impact for distros with older user-space. > > > > > > > > Is this issue also in 6.4-rc1 where this change came from? > > > > > > Yes. I'm reporting this here because I'm more concerned with -stable kernels since > > > they're more likely to be running on older user-space. > > > > Yeah, we are bug-compatible! :) > > > > When this gets fixed in Linus's tree, I'll be glad to backport the > > changes to the other kernels. Please work with the developers to get > > that fixed there. > > OK, I'll report it there, but shouldn't we avoid regressing -stable kernels? We should avoid regressing Linus's kernel tree just as much. It's always been this way, I don't want to revert patches unless they are really bad if the fix is not in Linus's tree already. Gives people "encouragement" to resolve the issue quicker. thanks, greg k-h
