Messages in this thread | | | Date | Wed, 29 Mar 2023 14:34:16 +0300 | From | Leon Romanovsky <> | Subject | Re: [PATCH net v2] net: ipa: compute DMA pool size properly |
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On Tue, Mar 28, 2023 at 11:08:33AM -0500, Alex Elder wrote: > In gsi_trans_pool_init_dma(), the total size of a pool of memory > used for DMA transactions is calculated. However the calculation is > done incorrectly. > > For 4KB pages, this total size is currently always more than one > page, and as a result, the calculation produces a positive (though > incorrect) total size. The code still works in this case; we just > end up with fewer DMA pool entries than we intended. > > Bjorn Andersson tested booting a kernel with 16KB pages, and hit a > null pointer derereference in sg_alloc_append_table_from_pages(), > descending from gsi_trans_pool_init_dma(). The cause of this was > that a 16KB total size was going to be allocated, and with 16KB > pages the order of that allocation is 0. The total_size calculation > yielded 0, which eventually led to the crash. > > Correcting the total_size calculation fixes the problem. > > Reported-by: Bjorn Andersson <quic_bjorande@quicinc.com> > Tested-by: Bjorn Andersson <quic_bjorande@quicinc.com> > Fixes: 9dd441e4ed57 ("soc: qcom: ipa: GSI transactions") > Signed-off-by: Alex Elder <elder@linaro.org> > --- > Note: This was reported via private communication. > v2: - Added Bjorn's actual name to tags.
You discarded Mark's Reviewed-by tag.
> > drivers/net/ipa/gsi_trans.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) >
Thanks, Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
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