In D17860#384464, @kib wrote:

Well, exactly the same symptom (hanging sched_bind()) happen on Apollo Lake due to the hardware bug, see r333026. Problem was that a write did not wake up the core in MWAIT, and no interrupts were generated yet.

I do not know what idling method is selected for your machine, try to switch to something different. For instance, Ryzens have an errata 1057 (and possibly 1109) which is almost identical to Apollo Lake issue.

In D17860#384153, @mmacy wrote:

Why isn’t this hit elsewhere? Are you compiling without EARLY_AP ?

options EARLY_AP_STARTUP is enabled..
this is not easy to reproduce, as AMD EPYC 7501 has 64 core's some how sched_bind creating problem during pci_release_msi(dev)
I am think sched_bind is not required during IRQ's assignment.
The actual root cause is unknown.

In D17401#373713, @mmacy wrote:

In D17401#373706, @somalapuram_gmail.com wrote:

In D17401#373648, @mmacy wrote:

Do you need this in for the 12 release? I can do that, it just means some more hoops for me jump through.

I am unable to commit (svn commit). (https://wiki.freebsd.org/Phabricator)

Do I have to commit or it will be automatically do ?? do I miss any steps ??

svn-commit.tmp: 36 lines, 1596 characters.
svn: E170001: Commit failed (details follow):
svn: E170001: Authorization failed
svn: E170001: Your commit message was left in a temporary file:
svn: E170001: '/usr/home/amar/freebsd_svn/freebsd_head/svn-commit.tmp'

Someone with a commit bit needs to do it

In D17401#373648, @mmacy wrote:

Do you need this in for the 12 release? I can do that, it just means some more hoops for me jump through.

I am unable to commit (svn commit). (https://wiki.freebsd.org/Phabricator)

In D17401#373648, @mmacy wrote:

Do you need this in for the 12 release? I can do that, it just means some more hoops for me jump through.

Can you please review this.

updated the code

updated the code

<<hwpmc> Add library and kernel support for AMD Family 17h new counters L3 Cache and Data Fabric

In D17427#371711, @mmacy wrote:

Is there a reason you didn't just update the diff on the existing review?