Hi, Just a friendly reminder that this issue still happens on Linux 6.8 and reverting commit 9b2f753ec237 as indicated below is still sufficient to resolve the problem. On 2023-01-21 08:31, Linux kernel regression tracking (Thorsten Leemhuis) wrote: > CCing the sparc maintainer. Also CCing the regression list, as it should > be in the loop for regressions: > https://docs.kernel.org/admin-guide/reporting-regressions.html > > The the mail address of the culprit's author bounces. There is another > Atish Patra still active; does anyone known if those two are the same > person? > > Anyway, that's it from my side. [...] > On 20.01.23 04:15, Nick Bowler wrote: >> Hi, >> >> I'm resending this report CC'd to linux-kernel as there was no response >> on the sparclinux list. >> >> I tried 6.2-rc4 and there is no change in behaviour. Reverting the >> indicated commit still works to fix the problem. >> >> On 2022-07-12, Nick Bowler <nbowler@xxxxxxxxxx> wrote: >>> When using newer kernels on my Ultra 60 with dual 450MHz UltraSPARC-II >>> CPUs, I noticed that only CPU 0 comes up, while older kernels (including >>> 4.7) are working fine with both CPUs. >>> >>> I bisected the failure to this commit: >>> >>> 9b2f753ec23710aa32c0d837d2499db92fe9115b is the first bad commit >>> commit 9b2f753ec23710aa32c0d837d2499db92fe9115b >>> Author: Atish Patra <atish.patra@xxxxxxxxxx> >>> Date: Thu Sep 15 14:54:40 2016 -0600 >>> >>> sparc64: Fix cpu_possible_mask if nr_cpus is set >>> >>> This is a small change that reverts very easily on top of 5.18: there is >>> just one trivial conflict. Once reverted, both CPUs work again. >>> >>> Maybe this is related to the fact that the CPUs on this system are >>> numbered CPU0 and CPU2 (there is no CPU1)? >>> >>> Here is /proc/cpuinfo on a working kernel: >>> >>> % cat /proc/cpuinfo >>> cpu : TI UltraSparc II (BlackBird) >>> fpu : UltraSparc II integrated FPU >>> pmu : ultra12 >>> prom : OBP 3.23.1 1999/07/16 12:08 >>> type : sun4u >>> ncpus probed : 2 >>> ncpus active : 2 >>> D$ parity tl1 : 0 >>> I$ parity tl1 : 0 >>> cpucaps : flush,stbar,swap,muldiv,v9,mul32,div32,v8plus,vis >>> Cpu0ClkTck : 000000001ad31b4f >>> Cpu2ClkTck : 000000001ad31b4f >>> MMU Type : Spitfire >>> MMU PGSZs : 8K,64K,512K,4MB >>> State: >>> CPU0: online >>> CPU2: online >>> >>> And on a broken kernel: >>> >>> % cat /proc/cpuinfo >>> cpu : TI UltraSparc II (BlackBird) >>> fpu : UltraSparc II integrated FPU >>> pmu : ultra12 >>> prom : OBP 3.23.1 1999/07/16 12:08 >>> type : sun4u >>> ncpus probed : 2 >>> ncpus active : 1 >>> D$ parity tl1 : 0 >>> I$ parity tl1 : 0 >>> cpucaps : flush,stbar,swap,muldiv,v9,mul32,div32,v8plus,vis >>> Cpu0ClkTck : 000000001ad31861 >>> MMU Type : Spitfire >>> MMU PGSZs : 8K,64K,512K,4MB >>> State: >>> CPU0: online >>> >>> Let me know if you need any more info. >>> >>> Thanks, >>> Nick
