Messages in this thread |  | | Subject | Re: mmap(MAP_SHARED | MAP_ANON) broke! | From | (Eric W. Biederman) | Date | 11 Jan 1997 06:04:05 -0600 |
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>>>>> "Sujal" == Sujal Patel <smpatel@prognet.com> writes:
Sujal> On Fri, 10 Jan 1997, Mark Hemment wrote: >> I guess you need this so that the anon mapped pages are not marked >> COW upon fork().
Sujal> Correct.
>> There might be another problem, or two, but if you have enough >> memory just try changing do_mmap() and see what happens.
There is also another solution (That's a real hack). x = mmap(..., MAP_ANON |MAP_PRIVATE, ...); fd = open("/proc/self/mem"); y = mmap(...., MAP_SHARED, ..., fd, x); munmap(x);
There are some problems with this multiple mappings at different adresses may have some problems, and it isn't a supported linux feature. But for the moment it seems to work alright.
This might also be useful. I wish someone could trace through the kernel and get whatever about the above sequence that works into the regular mmap command. Oh, well.
Eric
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