Re: [PATCH 05/13] efi/x86: don't map the entire kernel text RW for mixed mode

From: Jiri Slaby <jslaby@suse.cz>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Gary Lin <glin@suse.com>, linux-efi <linux-efi@vger.kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Anshuman Khandual <anshuman.khandual@arm.com>,
	Arnd Bergmann <arnd@arndb.de>,
	Dan Williams <dan.j.williams@intel.com>,
	Dave Young <dyoung@redhat.com>,
	Saravana Kannan <saravanak@google.com>
Subject: Re: [PATCH 05/13] efi/x86: don't map the entire kernel text RW for mixed mode
Date: Thu, 9 Apr 2020 10:34:46 +0200	[thread overview]
Message-ID: <d38fd829-b944-da10-58c0-180f80e8264d@suse.cz> (raw)
In-Reply-To: <CAMj1kXFHUusU9dDgqhU_qswDVgYWx_kpaDEroj4ZSt3hr-AFsA@mail.gmail.com>

On 09. 04. 20, 10:19, Ard Biesheuvel wrote:
>>>> $ rpm -qlp ~/Downloads/ovmf-202002-1.1.i586.rpm
>>>> warning: /home/ardbie01/Downloads/ovmf-202002-1.1.i586.rpm: Header V3
>>>> RSA/SHA256 Signature, key ID 3dbdc284: NOKEY
>>>> /usr/share/doc/packages/ovmf
>>>> /usr/share/doc/packages/ovmf/README
>>>
>>> Hmmm, it's weird that OBS doesn't list all derived files.
>>> Anyway, the ia32 ovmf is available in
>>> http://download.opensuse.org/tumbleweed/repo/oss/noarch/qemu-ovmf-ia32-202002-1.1.noarch.rpm
>>
>> It indeed does:
>> https://build.opensuse.org/package/binaries/openSUSE:Factory/ovmf/standard
>>
>> Note that the ia32 version is noarch, built on i586.
>>
> 
> I am not able to reproduce this issue using the linked firmware image
> and a 5.6 x86_64_defconfig with efivarfs built in.

Yeah, I had to use the distro config too. Not sure what the trigger is.
Maybe some NUMA configs or something.

> Could anyone share the full log, please, along with the kernel config
> that was used?

Both uploaded:
http://decibel.fi.muni.cz/~xslaby/err/

Note that I switched the for-me-necessary =m configs to =y. So that it
is enough to build bzImage, w/o modules...

> Also, it would be good to know if it is reproducible
> using a kernel built from upstream.

Sure, I was bisecting the upstream kernel:
git bisect start
# bad: [7111951b8d4973bda27ff663f2cf18b663d15b48] Linux 5.6
git bisect bad 7111951b8d4973bda27ff663f2cf18b663d15b48
# good: [d5226fa6dbae0569ee43ecfc08bdcd6770fc4755] Linux 5.5
git bisect good d5226fa6dbae0569ee43ecfc08bdcd6770fc4755
# skip: [9f68e3655aae6d49d6ba05dd263f99f33c2567af] Merge tag
'drm-next-2020-01-30' of git://anongit.freedesktop.org/drm/drm
git bisect skip 9f68e3655aae6d49d6ba05dd263f99f33c2567af
# good: [b4a4bd0f2629ec2ece7690de1b4721529da29871] irqchip/gic-v4.1: Add
VPE INVALL callback
git bisect good b4a4bd0f2629ec2ece7690de1b4721529da29871
# good: [c130d2dc93cd03323494d82dbe7b5fb0d101ab62] rcu: Rename some
instance of CONFIG_PREEMPTION to CONFIG_PREEMPT_RCU
git bisect good c130d2dc93cd03323494d82dbe7b5fb0d101ab62
# good: [0aee99a1ea53de1aedcf96a4d52d6161ffba011a] iio: gyro: adis16136:
rework locks using ADIS library's state lock
git bisect good 0aee99a1ea53de1aedcf96a4d52d6161ffba011a
# bad: [83576e32a71717d1912b7dcb247a0f15613272da] Merge branch
'macb-TSO-bug-fixes'
git bisect bad 83576e32a71717d1912b7dcb247a0f15613272da
# bad: [7ba31c3f2f1ee095d8126f4d3757fc3b2bc3c838] Merge tag
'staging-5.6-rc1' of
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
git bisect bad 7ba31c3f2f1ee095d8126f4d3757fc3b2bc3c838
# good: [f76e4c167ea2212e23c15ee7e601a865e822c291] net: phy: add default
ARCH_BCM_IPROC for MDIO_BCM_IPROC
git bisect good f76e4c167ea2212e23c15ee7e601a865e822c291
# bad: [bd2463ac7d7ec51d432f23bf0e893fb371a908cd] Merge
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
git bisect bad bd2463ac7d7ec51d432f23bf0e893fb371a908cd
# good: [e279160f491392f1345f6eb4b0eeec5a6a2ecdd7] Merge tag
'timers-core-2020-01-27' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect good e279160f491392f1345f6eb4b0eeec5a6a2ecdd7
# bad: [511fdb78442229ac11057b4a55c3f03c253c062f] Merge branch
'x86-mtrr-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect bad 511fdb78442229ac11057b4a55c3f03c253c062f
# bad: [2180f214f4a5d8e2d8b7138d9a59246ee05753b9] Merge branch
'locking-core-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect bad 2180f214f4a5d8e2d8b7138d9a59246ee05753b9
# good: [d99391ec2b42d827d92003dcdcb96fadac9d862b] Merge branch
'core-rcu-for-linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect good d99391ec2b42d827d92003dcdcb96fadac9d862b
# good: [57ad87ddce79b6d54f8e442d0ecf4b5bbe8c5a9e] Merge branch 'x86/mm'
into efi/core, to pick up dependencies
git bisect good 57ad87ddce79b6d54f8e442d0ecf4b5bbe8c5a9e
# good: [ac3c76cc6d6deef573dd8c14232f20c6aa744f83] efi/libstub/x86: Use
mandatory 16-byte stack alignment in mixed mode
git bisect good ac3c76cc6d6deef573dd8c14232f20c6aa744f83
# bad: [484a418d075488c6999528247cc711d12c373447] efi: Fix handling of
multiple efi_fake_mem= entries
git bisect bad 484a418d075488c6999528247cc711d12c373447
# bad: [1f299fad1e312947c974c6a1d8a3a484f27a6111] efi/x86: Limit EFI old
memory map to SGI UV machines
git bisect bad 1f299fad1e312947c974c6a1d8a3a484f27a6111
# good: [75fbef0a8b6b4bb19b9a91b5214f846c2dc5139e] x86/mm: Fix NX bit
clearing issue in kernel_map_pages_in_pgd
git bisect good 75fbef0a8b6b4bb19b9a91b5214f846c2dc5139e
# bad: [97bb9cdc32108036170d9d0d208257168f80d9e9] efi/x86: Avoid RWX
mappings for all of DRAM
git bisect bad 97bb9cdc32108036170d9d0d208257168f80d9e9
# bad: [d9e3d2c4f103200d87f2c243a84c1fd3b3bfea8c] efi/x86: Don't map the
entire kernel text RW for mixed mode
git bisect bad d9e3d2c4f103200d87f2c243a84c1fd3b3bfea8c
# first bad commit: [d9e3d2c4f103200d87f2c243a84c1fd3b3bfea8c] efi/x86:
Don't map the entire kernel text RW for mixed mode

thanks,
-- 
js
suse labs