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a=wKuvFiaSGQ0qltdbU6+NXLB8nM8=:19 a=Ol13hO9ccFRV9qXi2t6ftBPywas=:19 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=6IFa9wvqVegA:10 a=GoEa3M9JfhUA:10 a=8IXTDK3gWPi9ZSE4_WgA:9 a=CjuIK1q_8ugA:10 cc=ntf awl=host:13206 X-Proofpoint-GUID: gcf8HNrDewP-meTKgehQvk9YSuKNb_CY X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwNjA2MDA5NCBTYWx0ZWRfX7cZ7gw1+nhVS GOiSyNepWf9bXr3hr9Kslc3JO71d2bTNvKQGHrm6SdgEl1hY4rSiR7yXMFyvCEj3z/M5Zmnwgnk I9vJrDMw9f7dW+GmbU0c+2L5iFlCYBOb4D0MC2s/H6XkE0c8MoIXnoE0G3ci5WtlWn37MHutQLf xjVqCw2bQJiwcgvRdSFeX+sHdE4Qp0wb9WRb15o/JyMJzFQahDsUQhORAdzy5kfOgd+FGvUFEjQ i9b+OxRDQkubfUazP+Gu9Gamw0OIogOSrVS2dFX9ErdDZ+GFmUYhQejIzq64UZuaxGl4T5ZxJ6l 6Pav+7xuLAJpblnpd1oPFpnZCSpN922z/82vX5R/5MHU7nRmuWi/lpwM+oRfdxaS3uXp8/AXN7W m7b+lsRzQpWILu3zVGLWtG1lGSIO9FcBd5VojIhgYgMAvLhYOq9AMD+DJUkuihLODDJXfmxs X-Proofpoint-ORIG-GUID: gcf8HNrDewP-meTKgehQvk9YSuKNb_CY On Fri, Jun 06, 2025 at 12:13:27PM +0200, Michal Hocko wrote: > On Fri 06-06-25 11:01:18, David Hildenbrand wrote: > > On 06.06.25 10:31, Michal Hocko wrote: > [...] > > > Turning them into VM_WARN_ON > > > should be reasonably safe as they are not enabled in production > > > environment anyway so we cannot really rely on those. Having them in > > > WARN form would be still useful for debugging and those that really need > > > a crash dump while debugging can achieve the same result. > > > > One question is if we should be VM_WARN_ON vs. VM_WARN_ON_ONCE ... > > *WARN_ONCE ha a very limited use from code paths which are generally > shared by many callers. You just see one and then nothing. Some time ago > we have discussed an option to have _ONCE per call trace but I haven't > see any follow up. > > Anyway starting without _ONCE seems like safer option because we are not > losing potentially useful debugging information. Afterall this is > debugging only thing. But no strong position on my side. > > > VM_BUG_ON is essentially a "once" thing so far, but then, we don't continue > > ... so probably most should be _ONCE. > > > > > > > > So while I agree that many of them could be dropped or made more clear > > > those could be dealt with after a mass move. An advantage of this would > > > be that we can drop VM_BUG_ON* and stop new instances from being added. > > > > As a first step we could probably just #define them to go to the > > VM_WARN_ON_* variants and see what happens. > > You meand VM_BUG_ON expand to VM_WARN_ON by default? Sorry to interject in the conversation, but to boldly throw my two English pence into the mix: As the "king of churn" (TM) you'll not be surprised to hear that I'm in favour of us just doing a big patch and convert all VM_BUG_ON() -> VM_WARN_ON_ONCE() and remove VM_BUG_ON*(). Pull the band-aid off... I think better than a #define if this indeed what you meant David. But of course, you'd expect me to have this opinion ;) > > -- > Michal Hocko > SUSE Labs Cheers, Lorenzo