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 BD77D33077 for ; Fri, 24 Nov 2023 15:50:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Apo4IKoZ" Received: by smtp.kernel.org (Postfix) with ESMTPS id 8F3F3C433CD for ; Fri, 24 Nov 2023 15:50:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700841039; bh=Atjpf7PbSXCnxaMZxtpMQwok4N99LY8RvOFu4HjgPhk=; h=From:To:Subject:Date:In-Reply-To:References:From; b=Apo4IKoZqzFOqzqYitD5P2t1lCASoFUAt/w6XjQZroUD/HhYyzo3gJFpm5ihAPbj0 eWIVHDBhRCUpTZ6MGjGLd3d4wlVZvqA4SYmbi1qsd5lPcAzUUtj4pr5tM3RkK9Y1px D9dn+yL+JjrY6G7NFJCIN32evSjC/FIjGJwYFDrjSFpA4TaLwUg02bHjQlLsB94pwL 2QT0jC3YxZ3yA8pTjtMyfrFKVAC0muZ9PmPZnmbBtnmPqgemgFHdNUISCVlVy1OA2K 9KZVm5nOpbBZpfJNZrKc4j9b0yGx5t2FvCE2RTELmfbAOMMd+28n2sm6TRCbE5OpLi As14q3N34TU7A== Received: by aws-us-west-2-korg-bugzilla-1.web.codeaurora.org (Postfix, from userid 48) id 79AA0C53BCD; Fri, 24 Nov 2023 15:50:39 +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: Fri, 24 Nov 2023 15:50:39 +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 #26 from Alan Stern (stern@rowland.harvard.edu) --- "u8 (*buffer)[8]" means that buffer is a pointer to an array of 8 u8's, NOT= an array of 8 pointers to u8. The latter would be written as "u8 *(buffer[8])= " or "u8 *buffer[8]". C's syntax is notoriously difficult to understand when talking about arrays of pointers and pointers to arrays; you have to parse = the declaration from the inside out and you may need to know that postfix "[]" = has higher binding precedence than prefix "*". 1 and 4 don't map to anything; they are the _lengths_ of the DMA mappings.= =20 That is, the first mapping is 1 byte long and the second mapping is 4 bytes long: These are lengths in bytes, not in longs. --=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.=