Messages in this thread | | | Date | Tue, 29 Jan 2013 10:30:01 +0800 | From | Lingzhu Xiang <> | Subject | Re: [RFC] efivars write(2) races |
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On 01/28/2013 08:38 PM, Matt Fleming wrote: > On Mon, 2013-01-28 at 10:38 +0800, Lingzhu Xiang wrote: >> On 01/25/2013 09:18 PM, Matt Fleming wrote: >>>> 4. EFI_VARIABLE_APPEND_WRITE with EFI_OUT_OF_RESOURCES truncates size but you >>>> can still read its content. >>> >>> I'm not sure what you mean by this. Could you please explain? >> >> Oops, this one is incorrect. I was testing EFI_VARIABLE_APPEND_WRITE >> using this: >> >> printf "\x47\x00\x00\x00\x00" >test-1-$guid >> >> So it truncates the file before writing, but efivarfs figures out the right >> size afterwards. The size remains zero if the write fails. >> >> I should be using this for appending: >> >> printf "\x47\x00\x00\x00\x00" >>test-1-$guid > > Does this mean that these two test cases work as expected?
Mostly yes.
printf "\x47\x00\x00\x00\x00" >test-1-$guid
still shows unexpected truncate behavior. But this is the same one already noted previously (truncate doesn't actually work).
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