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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Jagdish Gediya' <jvgediya@linux.ibm.com>
CC:     "linux-mm@kvack.org" <linux-mm@kvack.org>,
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        "adobriyan@gmail.com" <adobriyan@gmail.com>
Subject: RE: [PATCH] kobject: Refactor kobject_set_name_vargs()
Thread-Topic: [PATCH] kobject: Refactor kobject_set_name_vargs()
Thread-Index: AQHYYU3qLELCyca9fE2SaEK1v39Vvq0R6/5wgAAc1ACAASXE8A==
Date:   Sat, 7 May 2022 10:01:03 +0000
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From: Jagdish Gediya
> Sent: 06 May 2022 18:24
...
> > Are you sure this can ever work from a module?
> > This all relies on:
> >
> > static inline bool is_kernel_rodata(unsigned long addr)
> > {
> > 	return addr >= (unsigned long)__start_rodata &&
> > 	       addr < (unsigned long)__end_rodata;
> > }
> >
> > which isn't going to do anything sane given an "xxx" inside a module.
> >
> > Indeed can kobject_set_name_vargs() end up with a constant string
> > inside a module?
> 
> No, kobject_set_name_vargs() is not exported. I exported
> set_name_vargs() because it can have a broader use, but you are right
> it shouldn't be exported.

I was thinking that some function that creates a 'kobject'
could easily be called from a module - so you end up calling
the set_name code from a module and then end up calling
kfree() on a literal from a module.

Now it might be that it is impossible to actually the quoted
literal from a module into somewhere that is_kernel_rodata()
is applied to.

But, as i said, it is fragile.

	David

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