From nobody Tue May 23 04:35:13 2023 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4QQM1d2g0Dz4T0Mw for ; Tue, 23 May 2023 04:35:17 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.95.76.21]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "troutmask", Issuer "troutmask" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4QQM1d1Q5wz3qK8 for ; Tue, 23 May 2023 04:35:17 +0000 (UTC) (envelope-from sgk@troutmask.apl.washington.edu) Authentication-Results: mx1.freebsd.org; none Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.17.1/8.17.1) with ESMTPS id 34N4ZEoF033272 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Mon, 22 May 2023 21:35:14 -0700 (PDT) (envelope-from sgk@troutmask.apl.washington.edu) Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.17.1/8.17.1/Submit) id 34N4ZDIR033271; Mon, 22 May 2023 21:35:13 -0700 (PDT) (envelope-from sgk) Date: Mon, 22 May 2023 21:35:13 -0700 From: Steve Kargl To: Warner Losh Cc: FreeBSD Hackers Subject: Re: gpart destroy efi partition? Message-ID: Reply-To: sgk@troutmask.apl.washington.edu References: List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 4QQM1d1Q5wz3qK8 X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:73, ipnet:128.95.0.0/16, country:US] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N On Mon, May 22, 2023 at 09:51:40PM -0600, Warner Losh wrote: > On Mon, May 22, 2023, 9:45 PM Steve Kargl > wrote: > > > Is there a secret incantation for destroying an EFI > > partition on a USB memstick? After installing FreeBSD, > > I would like to re-use a memstick, but > > > > % gpart destroy da0 > > gpart: geom 'da0': Read-only file system > > % gpart destroy -F da0 > > gpart: geom 'da0': Read-only file system > > % gpart show da0 > > => 40 60063664 da0 GPT (29G) > > 40 60063664 1 ms-basic-data (29G) > > % gpart delete -i 1 da0 > > gpart: geom 'da0': Read-only file system > > % dd if=/dev/zero of=/dev/da0 bs=1m > > dd: /dev/da0: Read-only file system > > > > What's mounted? > Nothing mounted other than the boot partition on an internal hard drive. I plugged the memstick into a usb port, and use gpart to list disk info. % df Filesystem 1M-blocks Used Avail Capacity Mounted on /dev/ada0p2 458231 62032 359539 15% / devfs 0 0 0 0% /dev ada0p1 is the EFI boot partition on the internal drive. ada0p3 is swap. % gpart list da0 Geom name: da0 modified: false state: OK fwheads: 255 fwsectors: 63 last: 60063703 first: 40 entries: 128 scheme: GPT Providers: 1. Name: da0p1 Mediasize: 30752595968 (29G) Sectorsize: 512 Stripesize: 0 Stripeoffset: 20480 Mode: r0w0e0 efimedia: HD(1,GPT,a2e07858-a4b6-11ec-ac6a-fcaa142bc587,0x28,0x3947fb0) rawuuid: a2e07858-a4b6-11ec-ac6a-fcaa142bc587 rawtype: ebd0a0a2-b9e5-4433-87c0-68b6b72699c7 label: (null) length: 30752595968 offset: 20480 type: ms-basic-data index: 1 end: 60063703 start: 40 Consumers: 1. Name: da0 Mediasize: 30752636928 (29G) Sectorsize: 512 Mode: r0w0e0 I did find % sysctl -a | grep da01 kern.geom.disk.da0.flags: 1a8 So, I suppose the question is how to clear WRITEPROTECT. -- Steve