Messages in this thread | | | Date | Thu, 04 Apr 2013 18:12:39 +0200 | From | Richard Weinberger <> | Subject | Re: [PATCH 1/2] efivars: Check max_size only if it is non-zero. |
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Am 04.04.2013 18:00, schrieb Luck, Tony: >> Some (broken?) EFI implementations return always a MaximumVariableSize of 0, >> check against max_size only if it is non-zero. > > The spec doesn't say that zero has any special meaning - so if an implementation > returns max_size == 0 but lets you set a variable to a size > 0, then I don't think > there is a need for parentheses or a "?" in this commit comment.
Thanks for the clarification. Yesterday I've looked into the spec, but the >2000 pages hurt my brain. ;-)
> But if Linux silently accepts such broken EFI, then there is no feedback loop > to let EFI implementations know that they are broken. In other areas we have > thrown out messages about firmware being broken ... perhaps: > > if (max_size == 0) > printk_once("Broken EFI implementation is returning MaxVariableSize=0\n"); > > would help? After all there probably *is* a maximum size - but EFI isn't telling us what it is.
Fair point. I'll add such a printk() to my patch and resend.
Thanks, //richard
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