From: Koichiro Den Date: Wed, 13 May 2026 02:49:20 +0000 (+0900) Subject: NTB: epf: Make db_valid_mask cover only real doorbell bits X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6eb7e28f1f24a28234add38755687a7ed8bc2654;p=thirdparty%2Flinux.git NTB: epf: Make db_valid_mask cover only real doorbell bits ndev->db_count includes an unused doorbell slot due to the legacy extra offset in the peer doorbell path. db_valid_mask must cover only the real doorbell bits and exclude the unused slot. Set db_valid_mask to BIT_ULL(db_count - 1) - 1. Fixes: 812ce2f8d14e ("NTB: Add support for EPF PCI Non-Transparent Bridge") Signed-off-by: Koichiro Den Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas Reviewed-by: Frank Li Reviewed-by: Dave Jiang Link: https://patch.msgid.link/20260513024923.451765-10-den@valinux.co.jp --- diff --git a/drivers/ntb/hw/epf/ntb_hw_epf.c b/drivers/ntb/hw/epf/ntb_hw_epf.c index 21d942824983..c0bab3292075 100644 --- a/drivers/ntb/hw/epf/ntb_hw_epf.c +++ b/drivers/ntb/hw/epf/ntb_hw_epf.c @@ -580,7 +580,11 @@ static int ntb_epf_init_dev(struct ntb_epf_dev *ndev) return ret; } - ndev->db_valid_mask = BIT_ULL(ndev->db_count) - 1; + /* + * ndev->db_count includes an extra skipped slot due to the legacy + * doorbell layout, hence -1. + */ + ndev->db_valid_mask = BIT_ULL(ndev->db_count - 1) - 1; ndev->mw_count = readl(ndev->ctrl_reg + NTB_EPF_MW_COUNT); ndev->spad_count = readl(ndev->ctrl_reg + NTB_EPF_SPAD_COUNT);