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Make cam_getccb(3) zero the whole ccb, not just the header
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Authored by trasz on Nov 23 2020, 1:33 PM.

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Summary

Make cam_getccb(3) zero the whole ccb, not just the header.

Leaving zeroing to the clients leads to error-prone pointer
tricks (zeroing needs to preserve the CCB header), and this
code is not performance-critical, so there's really no reason
to not do it.

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R10 FreeBSD src repository
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trasz requested review of this revision.Nov 23 2020, 1:33 PM
rpokala added a subscriber: rpokala.

LGTM, but I'm not authoritative when it comes to CAM.

I believe this is a good change. There's no performance reason to avoid zeroing, and in the kernel we do this:

new_ccb = malloc(sizeof(*new_ccb), M_CAMCCB, M_ZERO|M_WAITOK);

so this makes code that runs in both places more similar.

This revision is now accepted and ready to land.Nov 23 2020, 7:12 PM