On Mon, 2014-27-10 at 04:24:35 UTC, Ian Munsie wrote:

From: Ian Munsie <redacted>

In certain circumstances the PSL can send an interrupt for a segment

Define PSL before using it please.

miss that the kernel has already handled. This can happen if multiple
translations for the same segment are queued in the PSL before the
kernel has restarted the first translation.

The CXL driver did not expect this situation and did not check if a

does not and does not, you haven't patched it yet.

segment had already been handled. This could cause a duplicate segment
table entry which in turn caused a PSL error taking down the card.

This patch fixes the issue by checking for existing entries in the
segment table that match the segment it is trying to insert to avoid
inserting duplicate entries.

Some of the code has been refactored to simplify it - the segment table
hash has been moved from cxl_load_segment to find_free_sste where it is

Any reason that's not a separate patch?

used and we have disabled the secondary hash in the segment table to
reduce the number of entries that need to be tested from 16 to 8. Due to
the large segment sizes we use it is extremely unlikely that the
secondary hash would ever have been used in practice, so this should not
have any negative impacts and may even improve performance.

Any reason that's not a separate patch?

copro_calculate_slb will now mask the ESID by the correct mask for 1T vs

Didn't, but will after this patch?

256M segments. This has no effect by itself as the extra bits were
ignored, but it makes debugging the segment table entries easier and
means that we can directly compare the ESID values for duplicates
without needing to worry about masking in the comparison.

Separate patch?

cheers