Re: bioset changes in 4.18 broke aha1542

From: Ondrej Zary
Date: Thu Oct 18 2018 - 16:22:49 EST


On Thursday 18 October 2018 22:10:31 Jens Axboe wrote:
> On 10/18/18 2:04 PM, Ondrej Zary wrote:
> > On Thursday 18 October 2018 21:59:09 Jens Axboe wrote:
> >> On 10/18/18 1:55 PM, Ondrej Zary wrote:
> >>> On Thursday 18 October 2018 20:58:57 Jens Axboe wrote:
> >>>> On 10/18/18 12:34 PM, Ondrej Zary wrote:
> >>>>> Hello,
> >>>>> aha1542 works fine in 4.17 but crashes in 4.18. It's hard to bisect because
> >>>>> of many commits that don't compile.
> >>>>> # only skipped commits left to test
> >>>>> # possible first bad commit: [52190f8abe7f2bf2b4e5f9760cbcc1427ca2136b] fs: convert block_dev.c to bioset_init()
> >>>>> # possible first bad commit: [a47a28b74a5c7c27bf621276b85ad6c124651236] target: convert to bioset_init()/mempool_init()
> >>>>> # possible first bad commit: [6f1c819c219f7841079f0f43ab62727a55b0d849] dm: convert to bioset_init()/mempool_init()
> >>>>> # possible first bad commit: [afeee514ce7f4cab605beedd03be71ebaf0c5fc8] md: convert to bioset_init()/mempool_init()
> >>>>> # possible first bad commit: [d19936a26658a7a53edd5619d631ee2c2c3151a2] bcache: convert to bioset_init()/mempool_init()
> >>>>> # possible first bad commit: [b906bbb6997785d9ea0bd3f5585537afa6257c43] lightnvm: convert to bioset_init()/mempool_init()
> >>>>>
> >>>>> Testing manually, a47a28b74a5c7c27bf621276b85ad6c124651236 works.
> >>>>> 52190f8abe7f2bf2b4e5f9760cbcc1427ca2136b does not compile
> >>>>> 8ac9f7c1fd1d342e82ddf078425423b050652ba0 does not compile
> >>>>> e292d7bc63c8f2adb3dfda27910e805f1b6557f9 does not compile
> >>>>> dad08527525f9a8ac9c7f278864c65f94bc5e9b3 does not compile
> >>>>> 943cf9f3ca16133dbd00f9a4cbfea46512fcb0e8 works
> >>>>> ..
> >>>>> fedc3abe7bd2dcc4c80bcf3cff8708a3908d8219 works
> >>>>> 04c4950d5b373ba712d928592e05e73510785bca crashes
> >>>>
> >>>> It looks like the ISA bioset pool isn't being initialized. You should
> >>>> have messages like this in your dmesg:
> >>>>
> >>>> isa pool size: 16 pages
> >>>>
> >>>> (which you do), but also something on the bioset section. Do you have
> >>>> this one:
> >>>>
> >>>> pool size: 64 pages
> >>>>
> >>>> as well?
> >>>>
> >>>
> >>> No, it's not there.
> >>
> >> Can you attach your .config? I'm guessing CONFIG_HIGHMEM* isn't set.
> >>
> >
> > It is.
>
> Puzzled... Does this work?
>
>
> diff --git a/block/bounce.c b/block/bounce.c
> index b30071ac4ec6..49564a1bfd22 100644
> --- a/block/bounce.c
> +++ b/block/bounce.c
> @@ -35,10 +35,6 @@ static mempool_t page_pool, isa_page_pool;
> static __init int init_emergency_pool(void)
> {
> int ret;
> -#if defined(CONFIG_HIGHMEM) && !defined(CONFIG_MEMORY_HOTPLUG)
> - if (max_pfn <= max_low_pfn)
> - return 0;
> -#endif
>
> ret = mempool_init_page_pool(&page_pool, POOL_SIZE, 0);
> BUG_ON(ret);
>

Yes, it does!
bounce: pool size: 64 pages
and aha1542 works.

Also added printks for pfn:
max_pfn=65520, max_low_pfn=65520

--
Ondrej Zary