On 21/06/2023 14:49, Anna Schumaker wrote: > On Sat, Jun 17, 2023 at 6:09 AM Krzysztof Kozlowski > <krzysztof.kozlowski@xxxxxxxxxx> wrote: >> >> On 15/06/2023 21:38, Anna Schumaker wrote: >>> On Thu, Jun 15, 2023 at 1:16 PM Anna Schumaker <schumaker.anna@xxxxxxxxx> wrote: >>>> >>>> On Thu, Jun 15, 2023 at 1:04 PM Anna Schumaker <schumaker.anna@xxxxxxxxx> wrote: >>>>> >>>>> On Thu, Jun 15, 2023 at 9:01 AM Anna Schumaker <schumaker.anna@xxxxxxxxx> wrote: >>>>>> >>>>>> On Thu, Jun 15, 2023 at 4:55 AM Krzysztof Kozlowski >>>>>> <krzysztof.kozlowski@xxxxxxxxxx> wrote: >>>>>>> >>>>>>> On 15/06/2023 10:52, Krzysztof Kozlowski wrote: >>>>>>>> On 14/06/2023 22:55, Anna Schumaker wrote: >>>>>>>>>>>> Still null ptr (built on 420b2d4 with your patch): >>>>>>>>>>> >>>>>>>>>>> We're through the merge window and at rc1 now, so I can spend more >>>>>>>>>>> time scratching my head over your bug again. We've come up with a >>>>>>>>>>> patch (attached) that adds a bunch of printks to show us what the >>>>>>>>>>> kernel thinks is going on. Do you mind trying it out and letting us >>>>>>>>>>> know what gets printed out? You'll need to make sure >>>>>>>>>>> CONFIG_NFS_V4_2_READ_PLUS is enabled when compiling the kernel. >>>>>>>>>> >>>>>>>>>> The patch does not apply. I tried: v6.4-rc1, v6.4-rc5, next-20230609. >>>>>>>>> >>>>>>>>> Can you try the attached patch on top of my 3-patch series from the >>>>>>>>> other day, and let me know what gets printed out? It adds a bunch of >>>>>>>>> printk()s at strategic points to print out what is going on with the >>>>>>>>> xdr scratch buffer since it's suddenly a bad memory address after >>>>>>>>> working for a bit on your machine. >>>>>>>>> >>>>>>>> >>>>>>>> Here you have entire log - attached (113 kB, I hope goes past mailing >>>>>>>> lists/spam filters). >>>>>>> >>>>>>> As expected this bounced from the mailing lists, but I hope you got it. >>>>>>> If not, let me know. >>>>>> >>>>>> I did still receive it. Thanks! >>>>> >>>>> Can you swap out yesterday's patch with this patch? I've adjusted what >>>>> gets printed out, and added printk()s to xdr_copy_to_scratch(). I'm >>>>> starting to think that the xdr scratch buffer is fine, and that it's >>>>> the other pointer passed to memcpy() in that function that's the >>>>> problem, and the output from this patch will confirm for me. >>>> >>>> Oh, and can you add this one on top of the v2 patch as well? >>> >>> Sorry about the noise today. Can you use this patch instead of the two >>> I attached earlier? I cleaned up the output and cut down on extra >>> output.. >>> >> >> Here you have - attached. > > This is good, thanks! I was finally able to figure out how to hit the > bug using a 32bit x86 VM, so hopefully the next thing you hear from me > is a patch fixing the bug! QEMU also has 32-bit ARM and x86... Best regards, Krzysztof
