Messages in this thread | | | Subject | Re: [PATCH 4.19 000/219] 4.19.92-stable review | From | Guenter Roeck <> | Date | Wed, 1 Jan 2020 09:28:29 -0800 |
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On 1/1/20 8:24 AM, Greg Kroah-Hartman wrote: > On Tue, Dec 31, 2019 at 06:01:12PM -0800, Guenter Roeck wrote: >> On 12/30/19 9:35 AM, Greg Kroah-Hartman wrote: >>> On Mon, Dec 30, 2019 at 09:19:59AM -0800, Guenter Roeck wrote: >>>> On Sun, Dec 29, 2019 at 06:16:42PM +0100, Greg Kroah-Hartman wrote: >>>>> This is the start of the stable review cycle for the 4.19.92 release. >>>>> There are 219 patches in this series, all will be posted as a response >>>>> to this one. If anyone has any issues with these being applied, please >>>>> let me know. >>>>> >>>>> Responses should be made by Tue, 31 Dec 2019 16:17:25 +0000. >>>>> Anything received after that time might be too late. >>>>> >>>> Build results: >>>> total: 156 pass: 141 fail: 15 >>>> Failed builds: >>>> i386:tools/perf >>>> <all mips> >>>> x86_64:tools/perf >>>> Qemu test results: >>>> total: 381 pass: 316 fail: 65 >>>> Failed tests: >>>> <all mips> >>>> <all ppc64_book3s_defconfig> >>>> >>>> perf as with v4.14.y. >>>> >>>> arch/mips/kernel/syscall.c:40:10: fatal error: asm/sync.h: No such file or directory >>> >>> Ah, will go drop the offending patch and push out a -rc2 with both of >>> these issues fixed. >>> >>>> arch/powerpc/include/asm/spinlock.h:56:1: error: type defaults to ‘int’ in declaration of ‘DECLARE_STATIC_KEY_FALSE’ >>>> and similar errors. >>>> >>>> The powerpc build problem is inherited from mainline and has not been fixed >>>> there as far as I can see. I guess that makes 4.19.y bug-for-bug "compatible" >>>> with mainline in that regard. >>> >>> bug compatible is fun :( >>> >> >> Not really. It is a terrible idea and results in the opposite of what I would >> call a "stable" release. >> >> Anyway, turns out the offending commit is 14c73bd344d ("powerpc/vcpu: Assume >> dedicated processors as non-preempt"), which uses static_branch_unlikely(). > > It does? I see: > > + if (lppaca_shared_proc(get_lppaca())) > + static_branch_enable(&shared_processor); > >> This function does not exist for ppc in v4.19.y and v5.4.y. Thus, the _impact_ >> of the error in v4.19.y and v5.4.y is the same as in mainline, but the _cause_ >> is different. Upstream commit 14c73bd344d should not have been applied to >> v4.19.y and v5.4.y and needs to be reverted from those branches. > > I'll go revert this patch, but as it was marked for stable by the > authors of the patch, as relevant back to 4.18, I would have hoped that > they knew what they were doing :) >
I probably didn't have enough champagne last night when I wrote my previous e-mail. No, the problem is the same as with the upstream kernel, so feel free to drop the revert if you prefer "bug-for-bug compatibility". Given where we are, that is probably better than dropping the patch and re-applying it after its fix is available.
The underlying problem is that the offending patch introduces the use of jump label code into arch/powerpc/include/asm/spinlock.h without including linux/jump_label.h. Depending on the configuration, this results in the observed build errors.
Patches were submitted upstream to fix the problem, but the fix has not been applied to mainline, and I don't see a maintainer reaction. Maybe everyone is off for the holidays.
https://patchwork.ozlabs.org/patch/1215380/ https://patchwork.ozlabs.org/patch/1214954/
Guenter
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