From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC150C433EF for ; Wed, 13 Oct 2021 08:05:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2B9560EB4 for ; Wed, 13 Oct 2021 08:05:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238713AbhJMIHw (ORCPT ); Wed, 13 Oct 2021 04:07:52 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:56158 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233368AbhJMIHn (ORCPT ); Wed, 13 Oct 2021 04:07:43 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 563EC2228E; Wed, 13 Oct 2021 08:05:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1634112339; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MYBetIHiRnm5MPnYrU8m+s3sHrngXKaFc0Qug9OrkIs=; b=EjAzsDX2+zKTYfvf6tt1UnI74JTcYBLgT6njvzgUQGlmGCeEoRsvOeuV7f5wF7ORhcCLiM YJvYbI+0sv2xyxT5A73pPpWj/dPiRc9XmnRlf8tI/avsJgwb1JxVSqM3XfKddXE1mII69t jVbKFicq5fCtiYhBL9UWMEQcmAZWFzY= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1634112339; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=MYBetIHiRnm5MPnYrU8m+s3sHrngXKaFc0Qug9OrkIs=; b=uZAM7JtAcnRqCt2eGdlCK12fNcC034xOtUV5YyFXRy8Ra/5d9IJbFjVzxbNBrCqwdhiAQB 9VHc+iHjgaF8VFAA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 4CEB213CBE; Wed, 13 Oct 2021 08:05:39 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id X5uUElOTZmEvBgAAMHmgww (envelope-from ); Wed, 13 Oct 2021 08:05:39 +0000 MIME-Version: 1.0 Date: Wed, 13 Oct 2021 11:05:39 +0300 From: "Ivan T. Ivanov" To: Ard Biesheuvel Cc: Dominik Brodowski , linux-efi , Linux Kernel Mailing List Subject: Re: [RESEND] Re: [PATCH] Revert "efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness" In-Reply-To: References: <20211012082708.121931-1-iivanov@suse.de> <4eccf707f2553f0f66ae3789b5689231@suse.de> User-Agent: Roundcube Webmail Message-ID: X-Sender: iivanov@suse.de Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-10-13 10:50, Ard Biesheuvel wrote: > On Wed, 13 Oct 2021 at 09:30, Ivan T. Ivanov wrote: >> >> Hi, >> >> Quoting Dominik Brodowski (2021-10-12 11:40:34) >> > Am Tue, Oct 12, 2021 at 11:27:08AM +0300 schrieb Ivan T. Ivanov: >> > > This reverts commit 18b915ac6b0ac5ba7ded03156860f60a9f16df2b. >> > > >> > > When CONFIG_RANDOM_TRUST_BOOTLOADER is enabled add_bootloader_randomness() >> > > calls add_hwgenerator_randomness() which might sleep, >> > >> > Wouldn't it be better to fix add_bootloader_randomness(), considering >> > that >> > calls to that function are likely to happen quite early during kernel >> > initialization? Especially as it seems to have worked beforehand? >> >> I have tried. I made wait_event_interruptible() optional, but then >> crng_reseed() segfault badly. And I don't think crng_reseed() is >> something that I could fix easily. Suggestions are welcomed ;-) >> > > How about > > diff --git a/drivers/char/random.c b/drivers/char/random.c > index 605969ed0f96..1828dc691ebf 100644 > --- a/drivers/char/random.c > +++ b/drivers/char/random.c > @@ -2297,9 +2297,8 @@ EXPORT_SYMBOL_GPL(add_hwgenerator_randomness); > */ > void add_bootloader_randomness(const void *buf, unsigned int size) > { > + add_device_randomness(buf, size); > if (IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER)) > - add_hwgenerator_randomness(buf, size, size * 8); > - else > - add_device_randomness(buf, size); > + credit_entropy(&input_pool, size * 8); > } > EXPORT_SYMBOL_GPL(add_bootloader_randomness); This is more or less what I have done. credit_entropy() calls crng_reseed() which crash badly. Will check again, but I am sure it will give me same result. Regards, Ivan