On 2023/2/27 23:08, Linux regression tracking (Thorsten Leemhuis) wrote: > [CCing the regression list, as it should be in the loop for regressions: > https://docs.kernel.org/admin-guide/reporting-regressions.html] > > On 07.02.23 12:29, Will Deacon wrote: >> On Tue, Jan 31, 2023 at 05:03:32PM +0100, Ard Biesheuvel wrote: >>> On Tue, 31 Jan 2023 at 16:07, Will Deacon <will@xxxxxxxxxx> wrote: >>>> On Tue, Jan 31, 2023 at 03:06:44PM +0000, Will Deacon wrote: >>>>> On Sun, Jan 29, 2023 at 01:41:47PM -0800, Andrew Morton wrote: >>>>>> On Sun, 29 Jan 2023 10:44:31 +0800 Liu Shixin <liushixin2@xxxxxxxxxx> wrote: >>>>>>> On 2022/12/27 17:26, Liu Shixin wrote: >>>>>>>> After I add a 10GB pmem device, I got the following error message when >>>>>>>> insert module: >>>>>>>> >>>>>>>> insmod: vmalloc error: size 16384, vm_struct allocation failed, >>>>>>>> mode:0xcc0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0 >>>>>>>> >>>>>>>> If CONFIG_RANDOMIZE_BASE is set, the module region can be located in the >>>>>>>> vmalloc region entirely. Although module_alloc() can fall back to a 2GB >>>>>>>> window if ARM64_MODULE_PLTS is set, the module region is still easily >>>>>>>> exhausted because the module region is located at bottom of vmalloc region >>>>>>>> and the vmalloc region is allocated from bottom to top. >>>>>>>> >>>>>>>> Skip module region if not calling from module_alloc(). >>>>>> I'll assume this is for the arm tree. >>>>>> >>>>>> Acked-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> >>>>> This looks like the same issue previously reported at: >>>>> >>>>> https://lore.kernel.org/all/e6a804de-a5f7-c551-ffba-e09d04e438fc@xxxxxxxxxxxxx/ >>>>> >>>>> where Ard had a few suggestions but, afaict, they didn't help. >>>>> >>> Thanks for the cc. >>> >>> So this is a bit clunky, and I wonder whether we wouldn't be better >>> off just splitting the vmalloc region into two separate regions: one >>> for the kernel and modules, and one for everything else. That way, we >>> lose one bit of entropy in the randomized placement, but the default >>> 48-bit VA space is vast anway, and even on 39-bit VA configs (such as >>> Android), I seriously doubt that we come anywhere close to exhausting >>> the vmalloc space today. >> That sounds like a good idea to me. >> >> Liu Shixin -- do you think you could have a go at implementing Ard's >> suggestion instead? > Liu Shixin, did you ever look into realizing this idea? This is in my work list, but I haven't implemented it yet. Sorry for the long delay. > Or was some progress already made and I just missed it? > > I'm asking, as the idea discussed afaics is not only supposed to fix the > regression you tried to address, but also one that is now three months > old and stalled since Mid-December -- which is really unfortunate, as > that's not how regressions should be handled. :-/ But well, it afaik was > caused by a patch from Ard, so it's obviously not your job to address > it. But it seems you were working on it. > > Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat) > -- > Everything you wanna know about Linux kernel regression tracking: > https://linux-regtracking.leemhuis.info/about/#tldr > If I did something stupid, please tell me, as explained on that page. > > . >
