willy@thepuffingroup.com wrote:
> On Mon, Jan 31, 2000 at 03:56:03AM +0100, Patrick Mau wrote:
>> +/*
>> fds = (struct pollfd **)kmalloc(
>> (1 + (nfds - 1) / POLLFD_PER_PAGE) * sizeof(struct pollfd *),
>> GFP_KERNEL);
> (nfds * sizeof(void *) + POLLFD_PER_PAGE - 1) / POLLFD_PER_PAGE
Assuming that a struct pollfd * points to a page of pollfds, and fds is
an array of pointers, this is still wrong, e.g. assume nfds = 1,
sizeof(void *) = 4, POLLFD_PER_PAGE any value >= 2.
The original version yields a correct result and even seems a bit clearer,
unless nfds-1 becomes unsigned. In that case, something like
(nfds+POLLFD_PER_PAGE-1)/POLLFD_PER_PAGE*sizeof(struct pollfd *)
should help.
- Werner
-- _________________________________________________________________________ / Werner Almesberger, ICA, EPFL, CH werner.almesberger@ica.epfl.ch / /_IN_N_032__Tel_+41_21_693_6621__Fax_+41_21_693_6610_____________________/- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
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