From nobody Thu Mar 26 15:17:38 2026 X-Original-To: freebsd-virtualization@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 4fhS891kcGz6RgB6 for ; Thu, 26 Mar 2026 15:18:01 +0000 (UTC) (envelope-from chuck@tuffli.net) Received: from fhigh-b5-smtp.messagingengine.com (fhigh-b5-smtp.messagingengine.com [202.12.124.156]) (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 did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4fhS886c6vz3ppZ; Thu, 26 Mar 2026 15:18:00 +0000 (UTC) (envelope-from chuck@tuffli.net) Authentication-Results: mx1.freebsd.org; none Received: from phl-compute-06.internal (phl-compute-06.internal [10.202.2.46]) by mailfhigh.stl.internal (Postfix) with ESMTP id AC9017A0202; Thu, 26 Mar 2026 11:17:59 -0400 (EDT) Received: from phl-imap-17 ([10.202.2.105]) by phl-compute-06.internal (MEProxy); Thu, 26 Mar 2026 11:17:59 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tuffli.net; h=cc :cc:content-type:content-type:date:date:from:from:in-reply-to :in-reply-to:message-id:mime-version:references:reply-to:subject :subject:to:to; s=fm1; t=1774538279; x=1774624679; bh=KqRtCzvfMP K8Iqf96OpRfWLYJJqZ6m6mHrlTTs0lW18=; b=GT8Q3D0/R67Gxah3qsC0B0q/10 vwx17yFVlMB3eTQIblBGY3gkXu/T6eOC8X6EbqHfn736sZJ0EquEm1H/pXI1LPWw 2J05VYMd2+mbh6cSfCuDsCzHwfm/o9taKsp0GiM5OW8Eocfs7DFGYavxXv5A7kjj RSMr33DZZlLe7vjds/oKvIPDF2jJjILR/uHtqzCUalHCDpCDHQ8J0LnYaC20upRP oQgkuqYHarqMat/s15hnKa5kY5maZIMSb+bFocuekhdzH/isFFgMp4MmJPo0s5pU ULMbW5aiypSuVHCMfXOn8JBhKedixM8W1HSOEMqSMK9IcBJWv2/nblkol10A== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-type:content-type:date:date :feedback-id:feedback-id:from:from:in-reply-to:in-reply-to :message-id:mime-version:references:reply-to:subject:subject:to :to:x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm1; t= 1774538279; x=1774624679; bh=KqRtCzvfMPK8Iqf96OpRfWLYJJqZ6m6mHrl TTs0lW18=; b=Gnl3MY+iD4BPJ/UofeigdRhZ1OWDqeAwkOSU79BhiY19HHc/+sg Qi2HlWXUoA4nLJZdOwXNF+zSsMs4KyBE9XVeLAoaUtefGm3Lip/GWfsTjigruHGL KruypgvUFxR7XZ2HwJsu0aFcx/kLl/nUMCdHKaTsSsIcNWcl7Dx9gJE80C8yzoIg BvrKrhq1I0E+a1JtQoLjNbnGXM/YDjdt2osWLqnnraiB2l6Pn3yLCPQyXwwsnCC7 /ZVmX0X1kgobr/xMs8Jn0cgZnREEq1tZv9+/nAUQo/jvphC2ZAQDAyVgM2FyBlWt VkD2n0F+3aZunfr/+X63cDfpUzAD55uzNtQ== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeefgedrtddtgdefvdejjedvucetufdoteggodetrf dotffvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfurfetoffkrfgpnffqhgenuceu rghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujf gurhepofggfffhvfevkfgjfhfutgesrgdtreerredtjeenucfhrhhomhepfdevhhhutghk ucfvuhhffhhlihdfuceotghhuhgtkhesthhufhhflhhirdhnvghtqeenucggtffrrghtth gvrhhnpedvuefgudehleeuheehheetteelgfejiedtvdejheelvdekiedutefhieeigffg gfenucffohhmrghinhepfhhrvggvsghsugdrohhrghenucevlhhushhtvghrufhiiigvpe dtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegthhhutghksehtuhhffhhlihdrnhgvthdp nhgspghrtghpthhtohepfedpmhhouggvpehsmhhtphhouhhtpdhrtghpthhtohepfhhrvg gvsghsugdqvhhirhhtuhgrlhhiiigrthhiohhnsehfrhgvvggsshgurdhorhhgpdhrtghp thhtohepmhgrrhhkjhesfhhrvggvsghsugdrohhrghdprhgtphhtthhopehsvggrnhdrfh grghgrnheskhhlrghrrghshihsthgvmhhsrdgtohhm X-ME-Proxy: Feedback-ID: ib6f94606:Fastmail Received: by mailuser.phl.internal (Postfix, from userid 501) id 1AD97C40071; Thu, 26 Mar 2026 11:17:59 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface List-Id: Discussion List-Archive: https://lists.freebsd.org/archives/freebsd-virtualization List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: freebsd-virtualization@freebsd.org Sender: owner-freebsd-virtualization@FreeBSD.org MIME-Version: 1.0 X-ThreadId: Af1tmuC_I1Fw Date: Thu, 26 Mar 2026 08:17:38 -0700 From: "Chuck Tuffli" To: "Sean Eric Fagan" , "FreeBSD virtualization" Cc: "markj@freebsd.org" Message-Id: <0de221d3-40e5-431c-826f-4ba22c20ca17@app.fastmail.com> In-Reply-To: References: Subject: Re: bhyve and controlled errors Content-Type: multipart/alternative; boundary=1e641218b7464c31ade0e26c26006071 X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:151847, ipnet:202.12.124.0/24, country:AU] X-Rspamd-Queue-Id: 4fhS886c6vz3ppZ X-Spamd-Bar: ---- --1e641218b7464c31ade0e26c26006071 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Thu, Mar 26, 2026, at 7:56 AM, Sean Eric Fagan wrote: > I=E2=80=99d asked Mark about this and he suggested I bring it up on th= e list: >=20 > Has anyone thought about implementing controls / tunables to bhyve to = introduce errors? I am, most specifically right now, thinking about caus= ing disk I/O errors, or having requests dropped by the "hardware," to te= st error handling. >=20 > Last time I looked at the bhyve source code, it scared me, so if someo= ne else has looked at this, I=E2=80=99m love to know. I prototyped something like this a few years back https://papers.freebsd.org/2019/bsdcan/tuffli-frankensteins_disk_drive/ Happy to discuss it more if you are interested.=20 =E2=80=94chuck=20 --1e641218b7464c31ade0e26c26006071 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable


On Thu, Mar 26, 2026, at 7:56 AM, Sean Eric Fagan wrot= e:
I=E2=80=99d = asked Mark about this and he suggested I bring it up on the list:
<= div>
Has anyone thought about implementing controls / tuna= bles to bhyve to introduce errors? I am, most specifically right now, th= inking about causing disk I/O errors, or having requests dropped by the = "hardware," to test error handling.

Last time I= looked at the bhyve source code, it scared me, so if someone else has l= ooked at this, I=E2=80=99m love to know.

=
I prototyped something like this a few years back
<= br>

Happy to discuss = it more if you are interested. 

=E2=80=94c= huck 
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