Re: [PATCH] arch/{mips,sparc,microblaze,powerpc}: Don't enable pagefault/preempt twice

[Ira Weiny]

On Tue, May 19, 2020 at 09:54:22AM -0700, Guenter Roeck wrote:
> On Mon, May 18, 2020 at 11:48:43AM -0700, ira.weiny@xxxxxxxxx wrote:
> > From: Ira Weiny <ira.weiny@xxxxxxxxx>
> > 
> > The kunmap_atomic clean up failed to remove one set of pagefault/preempt
> > enables when vaddr is not in the fixmap.
> > 
> > Fixes: bee2128a09e6 ("arch/kunmap_atomic: consolidate duplicate code")
> > Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
> 
> microblazeel works with this patch,

Awesome...  Andrew in my rush yesterday I should have put a reported by on the
patch for Guenter as well.

Sorry about that Guenter,
Ira

> as do the nosmp sparc32 boot tests,
> but sparc32 boot tests with SMP enabled still fail with lots of messages
> such as:
> 
> BUG: Bad page state in process swapper/0  pfn:006a1
> page:f0933420 refcount:0 mapcount:1 mapping:(ptrval) index:0x1
> flags: 0x0()
> raw: 00000000 00000100 00000122 00000000 00000001 00000000 00000000 00000000
> page dumped because: nonzero mapcount
> Modules linked in:
> CPU: 0 PID: 1 Comm: swapper/0 Tainted: G    B             5.7.0-rc6-next-20200518-00002-gb178d2d56f29 #1
> [f00e7ab8 :
> bad_page+0xa8/0x108 ]
> [f00e8b54 :
> free_pcppages_bulk+0x154/0x52c ]
> [f00ea024 :
> free_unref_page+0x54/0x6c ]
> [f00ed864 :
> free_reserved_area+0x58/0xec ]
> [f0527104 :
> kernel_init+0x14/0x110 ]
> [f000b77c :
> ret_from_kernel_thread+0xc/0x38 ]
> [00000000 :
> 0x0 ]
> 
> Code path leading to that message is different but always the same
> from free_unref_page().
> 
> Still testing ppc images.
> 
> Guenter