Re: git: ada1f577cc29 - main - bhyve/riscv: correctly handle empty masks and broadcast in SBI IPI/RFNC

From: Ruslan Bukin <br_at_FreeBSD.org>
Date: Mon, 02 Nov 2026 21:33:04 UTC
On Mon Nov 2, 2026 at 9:10 PM UTC, Jessica Clarke wrote:
> On 2 Nov 2026, at 21:07, Ruslan Bukin <br@FreeBSD.org> wrote:
>> 
>> The branch main has been updated by br:
>> 
>> URL: https://cgit.FreeBSD.org/src/commit/?id=ada1f577cc291336cbb69782075dbbf9fe746872
>> 
>> commit ada1f577cc291336cbb69782075dbbf9fe746872
>> Author:     Doongar Singh <doonbsd@gmail.com>
>> AuthorDate: 2026-11-02 20:58:53 +0000
>> Commit:     Ruslan Bukin <br@FreeBSD.org>
>> CommitDate: 2026-11-02 21:05:46 +0000
>> 
>>    bhyve/riscv: correctly handle empty masks and broadcast in SBI IPI/RFNC
>> 
>>    Bhyve treats an empty cpu set as an error which triggers MPASS panic in
>>    the guest. As per the SBI spec, empty masks should return SBI_SUCCESS,
>>    and a base of -1UL specifies a broadcast to all harts.  Fix both in
>>    vmm_sbi.c, clear a1 on return, and skip the SBI ecall in
>>    sbi_ipi_pic_ipi_send() if the mask is empty. Also add a NULL check in
>>    riscv_send_ipi().
>
> Please revert this so it can be landed as several minimal commits that
> each do one thing, not one big commit that does more things that
> necessary all at once. See my initial feedback on the revision, though
> I am still reading through the rest of it.
>

Sounds good. Was a bit in a hurry as bhyve guest currently does not boot
without some of these bugfixes.

Ruslan