February 2024 - coreboot - mail.coreboot.org

[coreboot - Bug #415] (New) RESOURCE_ALLOCATION_TOP_DOWN breaks edk2
by Sean Rhodes May 2, 2025

May 2, 2025

Issue #415 has been reported by Sean Rhodes. ---------------------------------------- Bug #415: RESOURCE_ALLOCATION_TOP_DOWN breaks edk2 https://ticket.coreboot.org/issues/415 * Author: Sean Rhodes * Status: New * Priority: Low * Target version: none * Start date: 2022-09-07 * Affected versions: master ---------------------------------------- CB:41957 enabled RESOURCE_ALLOCATION_TOP_DOWN by default, which stopped edk2 from booting. The commit has been reverted, so this ticket is just to post logs. ---Files-------------------------------- resource_allocatorv4.txt (94 KB) -- You have received this notification because you have either subscribed to it, or are involved in it. To change your notification preferences, please click here: https://ticket.coreboot.org/my/account

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[coreboot - Feature #420] (New) Use standard format of TPM event log
by Krystian Hebel Aug. 7, 2024

Aug. 7, 2024

Issue #420 has been reported by Krystian Hebel. ---------------------------------------- Feature #420: Use standard format of TPM event log https://ticket.coreboot.org/issues/420 * Author: Krystian Hebel * Status: New * Priority: Normal * Target version: none * Start date: 2022-10-12 * Related links: [1] https://trustedcomputinggroup.org/wp-content/uploads/TCG_PCClientImplementa… [2] https://trustedcomputinggroup.org/wp-content/uploads/TCG_PCClient_PFP_r1p05… ---------------------------------------- Currently coreboot uses proprietary format for TPM event log. TCG has standardized log formats, differently for TPM1.2 (aka legacy or SHA1) [1] and TPM2.0 (aka crypto agile) [2], both of which can be parsed by Linux kernel and exposed in sysfs. I don't know of any tool outside of cbmem which can parse coreboot format; this includes payloads which may be interested in continuing chain of trust started by coreboot. Another incompatibility is caused by vboot's assignment of PCRs. Roles of PCRs are roughly specified by TCG in both of mentioned documents, they are more or less compatible with each other, but not with current coreboot code. These changes could break assumptions made by existing platforms, so they should be made as Kconfig options. This is a tracking issue to collect subtasks that need to be done in order to support standard event log formats. -- You have received this notification because you have either subscribed to it, or are involved in it. To change your notification preferences, please click here: https://ticket.coreboot.org/my/account

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[coreboot - Feature #433] (New) Unify TPM drivers in coreboot
by Michał Żygowski April 24, 2024

April 24, 2024

Issue #433 has been reported by Michał Żygowski. ---------------------------------------- Feature #433: Unify TPM drivers in coreboot https://ticket.coreboot.org/issues/433 * Author: Michał Żygowski * Status: New * Priority: Normal * Target version: none * Start date: 2022-10-24 ---------------------------------------- Add an option to compile all drivers for TPM 1.2, 2.0 TIS and CRB. The motivation is to not build multiple coreboot ROMs for each possible TPM supported by the platform. The tasks would include: - runtime TPM detection (probing TPM_INTF_CAPABILITY and TPM_INTERFACE_ID) - rename the TPM driver functions, make them static and expose them as a driver structure, e.g. struct tpm_driver { void (*init)(void); int (*open)(void); int (*close)(void); int (*sendrecv)(const uint8_t *sendbuf, size_t send_size, uint8_t *recvbuf, size_t *recv_len); } - based on the detected TPM, hook the tpm_driver functions to provide the global TPM API: tis_open, tis_close, tis_init, tis_sendrecv. Some additional API to get vendor/device name could also be considered. -- You have received this notification because you have either subscribed to it, or are involved in it. To change your notification preferences, please click here: https://ticket.coreboot.org/my/account

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Critical bug in RTC code for a leap year
by Michał Żygowski Feb. 29, 2024

Feb. 29, 2024

Hi folks, Another leap year, another problem with RTC in firmwares :) This time, unfortunately, this kind of bugs hit coreboot. I have issued a patch that fixes off-by-one error in the days count in month for a leap year: https://review.coreboot.org/c/coreboot/+/80790 It is quite critical, because depending on build date, it may revert to some very old date, like January 2023 or even older (depending on how long you run on current firmware). That said, the consequences are enormous: from false-negative expired certificates, to problems with filesystems, etc. It is worth considering an emergency coreboot release, is it not? Best regards, -- Michał Żygowski Firmware Engineer GPG: 6B5BA214D21FCEB2 https://3mdeb.com | @3mdeb_com

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Re: Are we running libpayload unit tests in the CI?
by Martin Roth Feb. 29, 2024

Feb. 29, 2024

Hey Julius, Here's what we running: https://review.coreboot.org/plugins/gitiles/coreboot/+/refs/heads/main/util… Martin Feb 27, 2024 at 18:31 by jwerner(a)chromium.org: > Hi, > > We've had unit test support in libpayload for over two years now, but > I just noticed that it doesn't look like we're actually running them > in the CI? E.g. if I look through a test run like this > https://qa.coreboot.org/job/coreboot-gerrit/252761/testReport/(root)/ > I can't find them anywhere (most of them have confusingly similar > names with coreboot unit tests, but "fmap_locate_area-test" is a > unique one). > > Is that intended or an oversight? Would it be easy to fix? (I'm not > super familiar with how the tests are integrated into Jenkins, but the > libpayload framework is pretty much a direct copy of the coreboot > framework, so if we can run the coreboot ones hopefully it should be > easy to run the libpayload ones as well?) > _______________________________________________ > coreboot mailing list -- coreboot(a)coreboot.org > To unsubscribe send an email to coreboot-leave(a)coreboot.org >

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The road towards LTO: an update and a few question
by Arthur Heymans Feb. 28, 2024

Feb. 28, 2024

Hi community I picked up the good work done by Jacob Garber to implement link time optimization. The size gains are very substantial, with sometimes up to 15% reduction in binary size! Besides the size benefit it can make us a bit more lazy programmers: for instance we often put static inline functions in headers guarded by preprocessing depending on Kconfig options to not generate code we won't use. With LTO that can be relaxed a bit and the condition to do nothing can come from a separate linked object (at least I presume, I haven't tested). So to do LTO, both with clang and GCC, you use the compiler as a linker frontend, rather than invoke the linker directly. Object files that are optionally generated with the -flto flag to generate LTO optimized binaries. See https://review.coreboot.org/c/coreboot/+/40811 Jacob's patches dealt with GCC. I toyed around with clang. The clang linker frontend only works with LTO if using the GOLD or LLD linker. GCC can use the BFD linker we currently use, so that's an easy transition. Both those linkers, GOLD and LLD are less capable at parsing linker scripts than the BFD linker. Especially for the x86 bootblock, in which we do a lot of stuff, like ID, FIT pointer, ECFW pointer, early 16 bit code, ..., is complicated and those linkers fail on the arithmetics doing all that optimized linking. So my question would be, whether we want to support non BFD linkers and therefore not support all the magic in linker scripts we currently have. At most we are a few bytes less optimal than possible by for instance setting a good hardcoded size and offset of the early 16bit code rather than have the linker script optimize that. As a side note, LTO size gainz are bigger than what would be lost, by a large margin. https://review.coreboot.org/c/coreboot/+/80724/1/src/arch/x86/bootblock.ld is a crude example of how I got lld to be happy with the script. If non BFD linkers are acceptable, how do you propose we deal with it? When not using LTO you could in principle use a different linker of your choosing. Should we just move to lld to make sure CI is happy about linker scripts? Should it be an option, but then we won?t have CI being able to test it except on a few boards put in configs/ ? Maybe have both, but then change the default once LLD is known to work well enough? Sidenote: LLD is faster than BFD but linking is not an expensive step in coreboot anyway. Other more typical linker scripts like the ones you find on ARM and ARM64 platforms work just fine. There are some subtle differences e.g. https://review.coreboot.org/c/coreboot/+/80735 where the heap needs to be declared to not be loaded. There are a few issues though. LLD does not like the RISCV relocation symbols of libgcc.a... I read upstream bugreports about this issue, so maybe that will resolve itself. Same questions with LTO and CI. Should it be an option (IMO yes, as that's what both Linux and u-boot do) and which default settings do we want. For CI reasons LTO is a bit more strict and therefore useful, as the compiler frontend does throw more warnings than the plain linker when linking. What are your thoughts? Are there some caveats about linkers and LTO that are worth knowing, before moving forward? Kind regards Arthur

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Need help from anyone at Meraki/Cisco
by David Hendricks Feb. 28, 2024

Feb. 28, 2024

Hi folks, As discussed in the Feb. 21 coreboot leadership meeting [1][2], concerns have been raised about coreboot source code releases for certain Meraki switch products. Requests have been made to open-source(a)meraki.com (mailto:open-source@meraki.com) about this with limited success in the past (MX84, MX250), though current requests for MS350 have gone practically unanswered. Since this problem scales with the product line-up, it seems an engineering approach to get code published - preferably upstream - will be a better way to solve it rather than repeated requests or escalation to the SFC. We're looking for anyone from Meraki/Cisco who would like to solve this by getting the code published. Several members of the coreboot community have experience working at (or with) companies in similar situations, and we're willing to help with this process. A few quick ideas mentioned in the recent meeting include a packaging tool to remove unused modules, a repo or branch on coreboot.org to host Meraki changes if they can't be mainlined easily, a license package that can integrate with Meraki's OS installer, etc. It's great that coreboot is used on these products and we believe that the coreboot community and corporate users such as Meraki mutually benefit when everyone's rights are respected. We strongly prefer an engineering approach to compliance with the GPLv2, but will look to other options if progress can't be made. If anyone at Meraki/Cisco happens to be reading this, feel free to contact me privately. [1] https://docs.google.com/document/d/1NRXqXcLBp5pFkHiJbrLdv3Spqh1Hu086HYkKrgK… (https://docs.google.com/document/d/1NRXqXcLBp5pFkHiJbrLdv3Spqh1Hu086HYkKrgK…) [2] https://www.mail-archive.com/coreboot@coreboot.org/msg58333.html (https://www.mail-archive.com/coreboot@coreboot.org/msg58333.html)

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Are we running libpayload unit tests in the CI?
by Julius Werner Feb. 28, 2024

Feb. 28, 2024

Hi, We've had unit test support in libpayload for over two years now, but I just noticed that it doesn't look like we're actually running them in the CI? E.g. if I look through a test run like this https://qa.coreboot.org/job/coreboot-gerrit/252761/testReport/(root)/ I can't find them anywhere (most of them have confusingly similar names with coreboot unit tests, but "fmap_locate_area-test" is a unique one). Is that intended or an oversight? Would it be easy to fix? (I'm not super familiar with how the tests are integrated into Jenkins, but the libpayload framework is pretty much a direct copy of the coreboot framework, so if we can run the coreboot ones hopefully it should be easy to run the libpayload ones as well?)

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CHIP_NAME history
by ron minnich Feb. 26, 2024

Feb. 26, 2024

I notice in bfb11bec3b3fec638adf864a9b9b2cff6671fed8 that CHIP_NAME is gone. I am glad to see it go, but I figured a quick note on history would help. Back in the day, we had coreboot on systems with as little as 256 KiB of memory. That was hard. One of the build options was to have CHIP_NAME result in "", which saved the length of the string + 4 bytes (the pointer). This was, on occasion, the difference between fitting an image or overflowing. It mattered. So the comment: " It was decided to remove this macro altogether, as it does not do anything special and incurs a maintenance burden." is accurate now, since CHIP_NAME always returns the string. But in the era in which CHIP_NAME was created, this comment is not correct.

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Introducing OSFF ByteTalks - Online Webinars about OSF
by Christian Walter Feb. 26, 2024

Feb. 26, 2024

Hi coreboot community, The Open-Source Firmware Foundation (OSFF) is pleased to announce ByteTalks, a new series of online webinars focused on the open-source firmware community. ByteTalks aims to provide a platform for learning, sharing, and discussing the latest developments in open-source firmware. Each session features talks by experienced professionals, practical tutorials, and a chance for participants to ask questions and engage with the speakers. Whether you're deeply involved in firmware development or just interested in learning more about the field, ByteTalks offers valuable insights and connections to help you grow. Join us to explore the evolving world of open-source firmware together. Announcing OSFF ByteTalks Vol. 1: “*FSP Customization - Remove non-mandatory components in the Intel FSP*” In the realm of open-source firmware, creating a custom Firmware Support Package (FSP) binary is a pivotal step for developers aiming to enhance hardware compatibility and performance. The process involves understanding the hardware's initialization requirements, integrating coreboot or similar open-source firmware solutions, and customizing the FSP to meet specific system needs. Our guests Subrata and Vincent will talk about the process on customizing the Intel FSP and removing non-mandatory components. For more information, check out the event page here: https://osfw.foundation/events/bytetalks-vol.-1/ In case you have any questions, feel free to reach out to me. In case you are also interested in joining the ByteTalks series as a speaker, feel free to reach out to me as well :) Best, Chris -- *Christian Walter* Open-Source Firmware Foundation Email: christian.walter(a)osfw.foundation

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