From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7EBB3606A31D for ; Fri, 23 Oct 2026 14:01:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=S9yy8vKm Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 11DE5112B6B; Fri, 23 Oct 2026 14:01:54 +0000 (UTC) Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by gabe.freedesktop.org (Postfix) with ESMTPS id 4C9D9112B6B; Fri, 23 Oct 2026 14:01:48 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 43C9D60142; Fri, 23 Oct 2026 14:01:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 926BE1F01828; Fri, 23 Oct 2026 14:01:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792764107; bh=pMDvcJ/aH4HAGtBAeASTFzR8JI/KqXaCGla6OGwhCJw=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=S9yy8vKmxYUAwzJGuUbnEfBnkIZlgnLL3CS6p6ZgOswB7HyNr+aZplwBTLWxJN6ED kfoCuM8II0hutSNBT4Qob1yZgnLDhcgrFq+WV/99qBuvDXTjjTLV2eaUe61Fsqdzwm 81pYU0NZnvdEzY2vfxl2yooxSqh65Db1P9MtAPcrp8JVyTWwarv85+Baep9gpl4pA3 n9q7XZ8zDgQ4x/MOsozudKDcjBS03luKmxbTz9jEhV8CQJFJ9DZSTx+hK9Z92u7jog sJDuST7QDGPqJnzNnz6C3NIO2hTsIYKck4z3PXR2KCtLfUgez+dTiRHo2XbMDkjDbF 9bGkxTImeA8gg== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v7 6/9] drm/msm/dp: don't take extra references on multiple plug events To: "Dmitry Baryshkov" Cc: dri-devel@lists.freedesktop.org, linux-usb@vger.kernel.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-amlogic@lists.infradead.org, neil.armstrong@linaro.org In-Reply-To: <20261023-hpd-irq-events-v7-6-57a3aea3f09e@oss.qualcomm.com> References: <20261023-hpd-irq-events-v7-0-57a3aea3f09e@oss.qualcomm.com> <20261023-hpd-irq-events-v7-6-57a3aea3f09e@oss.qualcomm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Fri, 23 Oct 2026 14:01:46 +0000 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "Intel-gfx" X-Spam-Status: No, score=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: - [High] drm/msm/dp: msm_dp_hpd_plug_handle() skips hpd_high after detect() -- commit c63c7584ce165272a5840e2bdd5f618e2bd07d8f Author: Dmitry Baryshkov drm/msm/dp: don't take extra references on multiple plug events This commit skips further HPD plug events in msm_dp_hpd_plug_handle() if dp->plugged is already set, avoiding extra runtime PM references until an unplug event is received. > diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp= /dp_display.c > index fa8942922b533..ce919a26fba28 100644 > --- a/drivers/gpu/drm/msm/dp/dp_display.c > +++ b/drivers/gpu/drm/msm/dp/dp_display.c > @@ -412,6 +412,9 @@ static int msm_dp_hpd_plug_handle(struct msm_dp_displ= ay_private *dp) > =20 > guard(mutex)(&dp->plugged_lock); > =20 > + if (dp->plugged) > + return 0; [Severity: High] Can this cause msm_dp_display_process_hpd_high() to be skipped altogether when msm_dp_bridge_detect() runs before msm_dp_hpd_plug_handle()? In drivers/gpu/drm/display/drm_bridge_connector.c, drm_bridge_connector_detect_ctx() invokes the bridge detect callback immediately before notifying HPD: if (detect) { status =3D detect->funcs->detect(detect, connector); ... drm_bridge_connector_hpd_notify(connector, status, DRM_CONNECTOR_NO_EXTRA= _STATUS); } When a DisplayPort sink is connected and drm_bridge_connector_detect_ctx() runs (for example during boot-time connector probing, resume, or DRM_IOCTL_MODE_GETCONNECTOR before an HPD interrupt is processed), msm_dp_bridge_detect() reads DPCD into a local buffer and sets priv->plugged =3D true without calling msm_dp_display_process_hpd_high(): status =3D connector_status_connected; priv->plugged =3D true; When drm_bridge_connector_hpd_notify() -> msm_dp_bridge_hpd_notify() -> msm_dp_hpd_plug_handle() then runs, or when a subsequent HPD plug event arrives, this new check sees dp->plugged =3D=3D true and returns early. Because msm_dp_display_process_hpd_high() is never called, LTTPR, dp->panel->link_info, connector EDID, dp->link->sink_count, and dp->audio_supported remain uninitialized, causing msm_dp_bridge_get_modes() to return 0 modes, msm_dp_display_mode_valid() to reject modes with MODE_BAD, and msm_dp_display_prepare_link() to fail with -ENOTCONN. Also, at the end of msm_dp_hpd_plug_handle(): ret =3D msm_dp_display_process_hpd_high(dp); ... dp->plugged =3D true; return ret; dp->plugged is set to true even when msm_dp_display_process_hpd_high() fails, which with this early return prevents subsequent HPD plug events from retrying initialization. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261023-hpd-irq-ev= ents-v7-0-57a3aea3f09e@oss.qualcomm.com?part=3D6 From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 638F7606A339 for ; Fri, 23 Oct 2026 14:01:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=y9Cfy7ek; dkim=fail reason="signature verification failed" (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=S9yy8vKm DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date:References: In-Reply-To:Cc:To:Subject:From:Message-ID:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=KQA7zI4HEV4jo75hyAAFoYdxIq5Hat3ngfpTm4TKfsY=; b=y9Cfy7ekSK6WWm9Q6vrk64wVQT c4LO8+qnbDeYA5yaMk7vJA1NEswUl5vlNDQdzjMhAmKO9RcQTXQpV6OFS/AzO7iKiWv079f/ew73G B5UDoLSSWJrqZgWtuh32mYFWu4CidXEmrNvv0d+dLJBHlJC+OMqu2Yy+XqFiSQ+nwFRHleR5QGS1D C2qTk8ulB/AzhD2iDbXH4yIMNVWoIssIxUsQAjIdVE6TlsX957jWzZawJMn9IC/kRGEnEo7Vlz4lK SParYBkPH56mwTC2khHxTZQKe+iib+SiWj+dTGPW7WNTSbQkApYPWlWrb6hmzkcWfkdjjFV7kb+tB F7ZGlkfw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xKFqA-0000000GSdB-0aqM; Fri, 23 Oct 2026 14:01:50 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xKFq8-0000000GSch-0iab for linux-amlogic@lists.infradead.org; Fri, 23 Oct 2026 14:01:48 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 43C9D60142; Fri, 23 Oct 2026 14:01:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 926BE1F01828; Fri, 23 Oct 2026 14:01:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792764107; bh=pMDvcJ/aH4HAGtBAeASTFzR8JI/KqXaCGla6OGwhCJw=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=S9yy8vKmxYUAwzJGuUbnEfBnkIZlgnLL3CS6p6ZgOswB7HyNr+aZplwBTLWxJN6ED kfoCuM8II0hutSNBT4Qob1yZgnLDhcgrFq+WV/99qBuvDXTjjTLV2eaUe61Fsqdzwm 81pYU0NZnvdEzY2vfxl2yooxSqh65Db1P9MtAPcrp8JVyTWwarv85+Baep9gpl4pA3 n9q7XZ8zDgQ4x/MOsozudKDcjBS03luKmxbTz9jEhV8CQJFJ9DZSTx+hK9Z92u7jog sJDuST7QDGPqJnzNnz6C3NIO2hTsIYKck4z3PXR2KCtLfUgez+dTiRHo2XbMDkjDbF 9bGkxTImeA8gg== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v7 6/9] drm/msm/dp: don't take extra references on multiple plug events To: "Dmitry Baryshkov" Cc: dri-devel@lists.freedesktop.org, linux-usb@vger.kernel.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-amlogic@lists.infradead.org, neil.armstrong@linaro.org In-Reply-To: <20261023-hpd-irq-events-v7-6-57a3aea3f09e@oss.qualcomm.com> References: <20261023-hpd-irq-events-v7-0-57a3aea3f09e@oss.qualcomm.com> <20261023-hpd-irq-events-v7-6-57a3aea3f09e@oss.qualcomm.com> Date: Fri, 23 Oct 2026 14:01:46 +0000 X-BeenThere: linux-amlogic@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-amlogic" X-Spam-Status: No, score=-9.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 VGhhbmsgeW91IGZvciB5b3VyIGNvbnRyaWJ1dGlvbiEgU2FzaGlrbyBBSSByZXZpZXcgZm91bmQg MSBwb3RlbnRpYWwgaXNzdWUocykgdG8gY29uc2lkZXI6Ci0gW0hpZ2hdIGRybS9tc20vZHA6IG1z bV9kcF9ocGRfcGx1Z19oYW5kbGUoKSBza2lwcyBocGRfaGlnaCBhZnRlciBkZXRlY3QoKQotLQoK Y29tbWl0IGM2M2M3NTg0Y2UxNjUyNzJhNTg0MGUyYmRkNWY2MThlMmJkMDdkOGYKQXV0aG9yOiBE bWl0cnkgQmFyeXNoa292IDxkbWl0cnkuYmFyeXNoa292QG9zcy5xdWFsY29tbS5jb20+Cgpkcm0v bXNtL2RwOiBkb24ndCB0YWtlIGV4dHJhIHJlZmVyZW5jZXMgb24gbXVsdGlwbGUgcGx1ZyBldmVu dHMKClRoaXMgY29tbWl0IHNraXBzIGZ1cnRoZXIgSFBEIHBsdWcgZXZlbnRzIGluIG1zbV9kcF9o cGRfcGx1Z19oYW5kbGUoKSBpZgpkcC0+cGx1Z2dlZCBpcyBhbHJlYWR5IHNldCwgYXZvaWRpbmcg ZXh0cmEgcnVudGltZSBQTSByZWZlcmVuY2VzIHVudGlsIGFuCnVucGx1ZyBldmVudCBpcyByZWNl aXZlZC4KCj4gZGlmZiAtLWdpdCBhL2RyaXZlcnMvZ3B1L2RybS9tc20vZHAvZHBfZGlzcGxheS5j IGIvZHJpdmVycy9ncHUvZHJtL21zbS9kcC9kcF9kaXNwbGF5LmMKPiBpbmRleCBmYTg5NDI5MjJi NTMzLi5jZTkxOWEyNmZiYTI4IDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvZ3B1L2RybS9tc20vZHAv ZHBfZGlzcGxheS5jCj4gKysrIGIvZHJpdmVycy9ncHUvZHJtL21zbS9kcC9kcF9kaXNwbGF5LmMK PiBAQCAtNDEyLDYgKzQxMiw5IEBAIHN0YXRpYyBpbnQgbXNtX2RwX2hwZF9wbHVnX2hhbmRsZShz dHJ1Y3QgbXNtX2RwX2Rpc3BsYXlfcHJpdmF0ZSAqZHApCj4gIAo+ICAJZ3VhcmQobXV0ZXgpKCZk cC0+cGx1Z2dlZF9sb2NrKTsKPiAgCj4gKwlpZiAoZHAtPnBsdWdnZWQpCj4gKwkJcmV0dXJuIDA7 CgpbU2V2ZXJpdHk6IEhpZ2hdCkNhbiB0aGlzIGNhdXNlIG1zbV9kcF9kaXNwbGF5X3Byb2Nlc3Nf aHBkX2hpZ2goKSB0byBiZSBza2lwcGVkIGFsdG9nZXRoZXIKd2hlbiBtc21fZHBfYnJpZGdlX2Rl dGVjdCgpIHJ1bnMgYmVmb3JlIG1zbV9kcF9ocGRfcGx1Z19oYW5kbGUoKT8KCkluIGRyaXZlcnMv Z3B1L2RybS9kaXNwbGF5L2RybV9icmlkZ2VfY29ubmVjdG9yLmMsCmRybV9icmlkZ2VfY29ubmVj dG9yX2RldGVjdF9jdHgoKSBpbnZva2VzIHRoZSBicmlkZ2UgZGV0ZWN0IGNhbGxiYWNrCmltbWVk aWF0ZWx5IGJlZm9yZSBub3RpZnlpbmcgSFBEOgoKCWlmIChkZXRlY3QpIHsKCQlzdGF0dXMgPSBk ZXRlY3QtPmZ1bmNzLT5kZXRlY3QoZGV0ZWN0LCBjb25uZWN0b3IpOwoJCS4uLgoJCWRybV9icmlk Z2VfY29ubmVjdG9yX2hwZF9ub3RpZnkoY29ubmVjdG9yLCBzdGF0dXMsIERSTV9DT05ORUNUT1Jf Tk9fRVhUUkFfU1RBVFVTKTsKCX0KCldoZW4gYSBEaXNwbGF5UG9ydCBzaW5rIGlzIGNvbm5lY3Rl ZCBhbmQgZHJtX2JyaWRnZV9jb25uZWN0b3JfZGV0ZWN0X2N0eCgpCnJ1bnMgKGZvciBleGFtcGxl IGR1cmluZyBib290LXRpbWUgY29ubmVjdG9yIHByb2JpbmcsIHJlc3VtZSwgb3IKRFJNX0lPQ1RM X01PREVfR0VUQ09OTkVDVE9SIGJlZm9yZSBhbiBIUEQgaW50ZXJydXB0IGlzIHByb2Nlc3NlZCks Cm1zbV9kcF9icmlkZ2VfZGV0ZWN0KCkgcmVhZHMgRFBDRCBpbnRvIGEgbG9jYWwgYnVmZmVyIGFu ZCBzZXRzCnByaXYtPnBsdWdnZWQgPSB0cnVlIHdpdGhvdXQgY2FsbGluZyBtc21fZHBfZGlzcGxh eV9wcm9jZXNzX2hwZF9oaWdoKCk6CgoJc3RhdHVzID0gY29ubmVjdG9yX3N0YXR1c19jb25uZWN0 ZWQ7Cglwcml2LT5wbHVnZ2VkID0gdHJ1ZTsKCldoZW4gZHJtX2JyaWRnZV9jb25uZWN0b3JfaHBk X25vdGlmeSgpIC0+IG1zbV9kcF9icmlkZ2VfaHBkX25vdGlmeSgpIC0+Cm1zbV9kcF9ocGRfcGx1 Z19oYW5kbGUoKSB0aGVuIHJ1bnMsIG9yIHdoZW4gYSBzdWJzZXF1ZW50IEhQRCBwbHVnIGV2ZW50 CmFycml2ZXMsIHRoaXMgbmV3IGNoZWNrIHNlZXMgZHAtPnBsdWdnZWQgPT0gdHJ1ZSBhbmQgcmV0 dXJucyBlYXJseS4KCkJlY2F1c2UgbXNtX2RwX2Rpc3BsYXlfcHJvY2Vzc19ocGRfaGlnaCgpIGlz IG5ldmVyIGNhbGxlZCwgTFRUUFIsCmRwLT5wYW5lbC0+bGlua19pbmZvLCBjb25uZWN0b3IgRURJ RCwgZHAtPmxpbmstPnNpbmtfY291bnQsIGFuZApkcC0+YXVkaW9fc3VwcG9ydGVkIHJlbWFpbiB1 bmluaXRpYWxpemVkLCBjYXVzaW5nIG1zbV9kcF9icmlkZ2VfZ2V0X21vZGVzKCkKdG8gcmV0dXJu IDAgbW9kZXMsIG1zbV9kcF9kaXNwbGF5X21vZGVfdmFsaWQoKSB0byByZWplY3QgbW9kZXMgd2l0 aApNT0RFX0JBRCwgYW5kIG1zbV9kcF9kaXNwbGF5X3ByZXBhcmVfbGluaygpIHRvIGZhaWwgd2l0 aCAtRU5PVENPTk4uCgpBbHNvLCBhdCB0aGUgZW5kIG9mIG1zbV9kcF9ocGRfcGx1Z19oYW5kbGUo KToKCglyZXQgPSBtc21fZHBfZGlzcGxheV9wcm9jZXNzX2hwZF9oaWdoKGRwKTsKCS4uLgoJZHAt PnBsdWdnZWQgPSB0cnVlOwoKCXJldHVybiByZXQ7CgpkcC0+cGx1Z2dlZCBpcyBzZXQgdG8gdHJ1 ZSBldmVuIHdoZW4gbXNtX2RwX2Rpc3BsYXlfcHJvY2Vzc19ocGRfaGlnaCgpCmZhaWxzLCB3aGlj aCB3aXRoIHRoaXMgZWFybHkgcmV0dXJuIHByZXZlbnRzIHN1YnNlcXVlbnQgSFBEIHBsdWcgZXZl bnRzCmZyb20gcmV0cnlpbmcgaW5pdGlhbGl6YXRpb24uCgotLSAKU2FzaGlrbyBBSSByZXZpZXcg wrcgaHR0cHM6Ly9zYXNoaWtvLmRldi8jL3BhdGNoc2V0LzIwMjYxMDIzLWhwZC1pcnEtZXZlbnRz LXY3LTAtNTdhM2FlYTNmMDllQG9zcy5xdWFsY29tbS5jb20/cGFydD02CgpfX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpsaW51eC1hbWxvZ2ljIG1haWxpbmcg bGlzdApsaW51eC1hbWxvZ2ljQGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0cDovL2xpc3RzLmluZnJh ZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1hbWxvZ2ljCg==