From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CA69FA21 for ; Sat, 25 Nov 2023 02:03:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="e2OiIW83" Received: by smtp.kernel.org (Postfix) with ESMTPS id 46575C433CB for ; Sat, 25 Nov 2023 02:03:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700877798; bh=GnBWUkU+F+fLvPf1y4emFUyTJnAglZ+1o8Lj8ndkB/4=; h=From:To:Subject:Date:In-Reply-To:References:From; b=e2OiIW83XsT62o9TfiVua20akQuT0vrEm7mPaEg72vw4LtgpRSrbPFqDn9z7n4flp rNKWe79rUJmFNFh9BFNiiTRGm//Of/ERRLQwqRfMHevOnRYJvPMw1xvLj9vW1oRuEc ZBxssGzmrseqAZotyuBkqr9PoVjNr2GaF28gwvONUj+r0sOIiSoYlaTQWGdIzcm9lC +g0iCI6io+y76KnY8qpmLcWmvP/6ifxqyw/Y6BKin1bRt5x9ZZbQYwql9UNofHjily nNj2k/qXNAY8fFDcqYLhZq/SZ45MRKvqQCW9UoX5sq3WD2K+ArR1xFt7Z2NMl2WrnL R4nOr5Fq9+MfQ== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 31E1AC53BD3; Sat, 25 Nov 2023 02:03:18 +0000 (UTC) From: bugzilla-daemon@kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 215740] kernel warning: DMA-API: xhci_hcd: cacheline tracking EEXIST, overlapping mappings aren't supported Date: Sat, 25 Nov 2023 02:03:17 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: stern@rowland.harvard.edu X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 https://bugzilla.kernel.org/show_bug.cgi?id=3D215740 --- Comment #31 from Alan Stern (stern@rowland.harvard.edu) --- I don't know why my local test didn't reproduce the problem -- and I haven't tried to find out what's happening. My best guess is that the allocations = of hub->buffer and hub->status end up (by random chance) being non-adjacent, so they aren't in the same cache line. But I haven't even run the test patches attached to this bug report. Regardless, changing the allocation size to 64 merely hides the problem. T= he real problem is that the DMA debugging code is wrong and needs to be fixed.= It should not complain about two different mappings of the same cache line on = x86, unless the mappings actually overlap. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=