Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Roman Zippel
Hi, Martin Wilck wrote: > Hum - is there no simple way to determine whether a pointer is > a valid pointer to something returned by __get_free_pages ()? You are > right, S390 in particular seems to allow arbitrary addresses starting from > 0. M68k does so too, although the first page is never

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Martin Wilck
> PAGE_OFFSET definitely works for me, but a quick scan of the headers > suggests that non-sun3 m68k builds define PAGE_OFFSET as 0, as does > s390. Hum - is there no simple way to determine whether a pointer is a valid pointer to something returned by __get_free_pages ()? You are right, S390

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Jonathan Lundell
At 10:07 AM +0200 2001-06-27, Martin Wilck wrote: >On Tue, 26 Jun 2001, Jonathan Lundell wrote: > >> I use the hack myself, to implement a record-oriented file where the >> file position is a record number. I could probably live with >> PAGE_SIZE, but the current hack works fine with start

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Martin Wilck
On Tue, 26 Jun 2001, Jonathan Lundell wrote: > I use the hack myself, to implement a record-oriented file where the > file position is a record number. I could probably live with > PAGE_SIZE, but the current hack works fine with start bigger than > that, and it's possible that someone counts on

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Martin Wilck
On Tue, 26 Jun 2001, Jonathan Lundell wrote: I use the hack myself, to implement a record-oriented file where the file position is a record number. I could probably live with PAGE_SIZE, but the current hack works fine with start bigger than that, and it's possible that someone counts on it.

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Jonathan Lundell
At 10:07 AM +0200 2001-06-27, Martin Wilck wrote: On Tue, 26 Jun 2001, Jonathan Lundell wrote: I use the hack myself, to implement a record-oriented file where the file position is a record number. I could probably live with PAGE_SIZE, but the current hack works fine with start bigger than

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Martin Wilck
PAGE_OFFSET definitely works for me, but a quick scan of the headers suggests that non-sun3 m68k builds define PAGE_OFFSET as 0, as does s390. Hum - is there no simple way to determine whether a pointer is a valid pointer to something returned by __get_free_pages ()? You are right, S390 in

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-27 Thread Roman Zippel
Hi, Martin Wilck wrote: Hum - is there no simple way to determine whether a pointer is a valid pointer to something returned by __get_free_pages ()? You are right, S390 in particular seems to allow arbitrary addresses starting from 0. M68k does so too, although the first page is never used

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Mike Galbraith
On Tue, 26 Jun 2001, Martin Wilck wrote: > Hi, > > > Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ > > it. It's a very nice little hack to have around, and IKD uses it. > > I am not saying it should be removed. But IMO it is a legitimate (if > not the originally

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Jonathan Lundell
At 7:14 PM +0200 2001-06-26, Martin Wilck wrote: >Hi, > >> Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ >> it. It's a very nice little hack to have around, and IKD uses it. > >I am not saying it should be removed. But IMO it is a legitimate (if >not the originally

[PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Martin Wilck
Hi, > Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ > it. It's a very nice little hack to have around, and IKD uses it. I am not saying it should be removed. But IMO it is a legitimate (if not the originally intended) use of "start" to serve as a pointer to a memory

[PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Martin Wilck
Hi, Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ it. It's a very nice little hack to have around, and IKD uses it. I am not saying it should be removed. But IMO it is a legitimate (if not the originally intended) use of start to serve as a pointer to a memory area

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Jonathan Lundell
At 7:14 PM +0200 2001-06-26, Martin Wilck wrote: Hi, Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ it. It's a very nice little hack to have around, and IKD uses it. I am not saying it should be removed. But IMO it is a legitimate (if not the originally intended)

Re: [PATCH] proc_file_read() (Was: Re: proc_file_read() question)

2001-06-26 Thread Mike Galbraith
On Tue, 26 Jun 2001, Martin Wilck wrote: Hi, Shhh ;-) Last time that hack was mentioned, someone wanted to _remove_ it. It's a very nice little hack to have around, and IKD uses it. I am not saying it should be removed. But IMO it is a legitimate (if not the originally intended) use