Re: [PATCH v2] hfsplus: avoid crash on failed block map free

[Vyacheslav Dubeyko <slava@dubeyko.com>]

On Tue, 2012-11-13 at 14:34 -0800, Andrew Morton wrote:

[snip]
> 
> The code is missing a flush_dcache_page()?  We should have one in there
> after the CPU has modified userspace-mappable page contents.
> 

Yes, I think your comment is precious. But I feel a necessity to analyze
hfsplus driver code more deeply for proper fix of this issue. An
userspace-mappable page content is the main use-case for such fix. But
it exists the multi CPUs use-case. So, I need to think about correctness
of hfsplus driver for such use-case also, I think.  

> 
> btw, I still have question marks over your earlier patches:
> 
> hfsplus-add-on-disk-layout-declarations-related-to-attributes-tree.patch
> hfsplus-add-functionality-of-manipulating-by-records-in-attributes-tree.patch
> hfsplus-rework-functionality-of-getting-setting-and-deleting-of-extended-attributes.patch
> hfsplus-add-support-of-manipulation-by-attributes-file.patch
> hfsplus-add-support-of-manipulation-by-attributes-file-checkpatch-fixes.patch
> hfsplus-code-style-fixes-reworked-support-of-extended-attributes.patch
> 
> Christoph sounded unhappy, but the review discussion petered out?
> 

So, as you can see the discussion revives again. :-) And I need to
familiarize with implementation of xattrs in JFS before to answer again.
I had objection that we need to remember about using HFS+ volumes as
under Linux as under Mac OS X. Maybe, JFS implementation of xattrs to
change my vision.

With the best regards,
Vyacheslav Dubeyko.