On 8/1/25 08:13, Breno Leitao wrote: > Hello Dave, > > On Fri, Aug 01, 2025 at 07:52:17AM -0700, Dave Hansen wrote: >> On 8/1/25 05:31, Breno Leitao wrote: >>> Introduce a generic infrastructure for tracking recoverable hardware >>> errors (HW errors that are visible to the OS but does not cause a panic) >>> and record them for vmcore consumption. >> ... >> >> Are there patches for the consumer side of this, too? Or do humans >> looking at crash dumps have to know what to go digging for? >> >> In either case, don't we need documentation for this new ABI? > > I have considered this, but the documentation for vmcoreinfo > (admin-guide/kdump/vmcoreinfo.rst) solely documents what is explicitly > exposed by vmcore, which differs from the nature of these counters. > > Where would be a good place to document it?
I'm not picky. But you also didn't quite answer the question I was asking. Is this new data for humans or machines to read? >>> @@ -1690,6 +1691,9 @@ noinstr void do_machine_check(struct pt_regs *regs) >>> } >>> >>> out: >>> + /* Given it didn't panic, mark it as recoverable */ >>> + hwerr_log_error_type(HWERR_RECOV_MCE); >>> + >> >> Does "MCE" mean anything outside of x86? > > AFAIK this is a MCE concept. I'm not really sure what that response means. There are two problems here. First is that HWERR_RECOV_MCE is defined in arch-generic code, but it may never get used by anything other than x86 when CONFIG_X86_MCE. That also completely wastes space in your data structure when HWERR_RECOV_MCE=n. Not a huge deal as-is, but it's still a bit sloppy and wasteful. ... >>> + hwerr_data[src].count++; >>> + hwerr_data[src].timestamp = ktime_get_real_seconds(); >>> +} >>> +EXPORT_SYMBOL_GPL(hwerr_log_error_type); >> >> I'd also love to hear more about _actual_ users of this. Surely, someone >> hit a real world problem and thought this would be a nifty solution. Who >> was that? What problem did they hit? How does this help them? > > Yes, this has been extensively discussed in the very first version of > the patch. Borislav raised the same question, which was discussed in the > following link: > > https://lore.kernel.org/all/20250715125327.GGaHZPRz9QLNNO-7q8@fat_crate.local/ When someone raises a concern, we usually try to alleviate the concern in a way that is self-contained in the next posting. A cover letter with a full explanation would be one place to put the reasoning, for example. But expecting future reviewers to plod through all the old threads isn't really feasible.
