Reviewed-by: Glenn Miles <mil...@linux.ibm.com>
On Mon, 2025-05-12 at 13:10 +1000, Nicholas Piggin wrote:
> When pushing a context, any presented group interrupt should be
> redistributed before processing pending interrupts to present
> highest priority.
>
> This can occur when pushing the POOL ring when the valid PHYS
> ring has a group interrupt presented, because they share signal
> registers.
>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
> ---
> hw/intc/xive2.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/hw/intc/xive2.c b/hw/intc/xive2.c
> index 21cd07df68..392ac6077e 100644
> --- a/hw/intc/xive2.c
> +++ b/hw/intc/xive2.c
> @@ -945,8 +945,9 @@ static void xive2_tctx_need_resend(Xive2Router *xrtr,
> XiveTCTX *tctx,
> uint8_t nvp_blk, uint32_t nvp_idx,
> bool do_restore)
> {
> + uint8_t *sig_regs = xive_tctx_signal_regs(tctx, ring);
> uint8_t *regs = &tctx->regs[ring];
> - uint8_t ipb;
> + uint8_t ipb, nsr = sig_regs[TM_NSR];
> Xive2Nvp nvp;
>
> /*
> @@ -978,6 +979,11 @@ static void xive2_tctx_need_resend(Xive2Router *xrtr,
> XiveTCTX *tctx,
> /* IPB bits in the backlog are merged with the TIMA IPB bits */
> regs[TM_IPB] |= ipb;
>
> + if (xive_nsr_indicates_group_exception(ring, nsr)) {
> + /* redistribute precluded active grp interrupt */
> + g_assert(ring == TM_QW2_HV_POOL); /* PHYS ring has the grp interrupt
> */
> + xive2_redistribute(xrtr, tctx, xive_nsr_exception_ring(ring, nsr));
> + }
> xive2_tctx_process_pending(tctx, ring == TM_QW2_HV_POOL ?
> TM_QW3_HV_PHYS : ring);
> }
