There is no good faith exception for willful violations of a bankruptcy stay; it suffices that the IRS knew of the stay and intentionally violated it.
With regard to the protection against willful violation, a stay offers the same protections as a discharge order.
This standard was contemplated at enactment, so the implied waiver of sovereign immunity is exactly parallel.
Dissent: presumption is against the waiver of sovereign immunity. As "willful" modifies "violation," IRS must knowingly violate a valid stay or discharge.
http://media.ca1.uscourts.gov/pdf.opinions/17-1601P-01A.pdf
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.