On Thu Aug 15, 2024 at 4:53 PM CEST, Tom Lendacky wrote: > On 8/15/24 09:40, Diederik de Haas wrote: > > On Thu Aug 15, 2024 at 4:16 PM CEST, Tom Lendacky wrote: > >> On 8/15/24 08:56, Diederik de Haas wrote: > >>> I recently bought an Asus ROG STRIX B550-F GAMING MB with an > >>> AMD Ryzen 5 5500GT CPU (and installed the latest BIOS: 3607). > >>> I'm running Debian Testing/Sid on it with kernel 6.9 and now 6.10 > >>> and it seems to work great. > >>> I've been doing some (unrelated) tests with `rngtest` from the > >>> `rng-tools5` package and wondered how it would fare on my AMD CPU. > >> > >> I'm not very familiar with this test. What is the command line that you > >> are using to invoke it? > > > > ``` > > root@cs04:~# cat /dev/hwrng | rngtest -c 1000 > > rngtest 5 > > Copyright (c) 2004 by Henrique de Moraes Holschuh > > This is free software; see the source for copying conditions. > > There is NO warranty; not even for MERCHANTABILITY or FITNESS > > FOR A PARTICULAR PURPOSE. > > > > rngtest: starting FIPS tests... > > cat: /dev/hwrng: No such device > > rngtest: entropy source drained > > Ok, this makes sense since you are using /dev/hwrng. This device does > not exist because the CCP support in the ccp driver did not create one. > It appears that the BIOS has blocked access to the MMIO range for the > CCP so that during initialization, when attempting to read the number of > queues available, 0xffffffff is read instead of the actual number of > queues available, which as Jason noted, results in the "broken BIOS" > message. Ok, so the BIOS is broken. Good to know. Thanks :) > This may not matter, though. I don't know if this version of the ASP/CCP > device (1022:15df) provides any queues to the OS to use. But I don't know how to interpret this? I initially contacted Asus (HQ) and they apparently had contact with AMD about this. I was 'a bit' flabbergasted about the response though: "We have confirmed with AMD that the Linux system supported by the customer's CPU (AMD Ryzen 5 5500GT) is Ubuntu:20.04.x. The corresponding Linux Kernel version is between 5.4 and 5.8, and the customer's OS version is Linux Kernel version: 6.9.10. The CPU is not supported." I have no idea how Ubuntu 20.04 and kernel 5.4 got into that communication as I clearly said I tested it with Debian and kernel 6.9 and 6.10. Basically the same as here, except more extensive/detailed. > The fact that there is no /dev/hwrng device is not a kernel bug, though. > > Thanks, > Tom Thanks for the responses, much appreciated :-) Cheers, Diederik > > ``` > > > > Or when using ``dd`` you'd get a similar output: > > > > ``` > > root@cs04:~# dd if=/dev/hwrng bs%6 | rngtest -c 1000 > > rngtest 5 > > ... > > > > rngtest: starting FIPS tests... > > dd: error reading '/dev/hwrng': No such device > > 0+0 records in > > 0+0 records out > > rngtest: entropy source drained > > 0 bytes copied, 4.8214e-05 s, 0.0 kB/s > > `` > > > > Debian package page: https://packages.debian.org/unstable/rng-tools5 > > Debian hasn't switched to the new upstream (yet?), but that can be found > > here: https://github.com/nhorman/rng-tools > > > >>> And I found out it doesn't work at all! > >>> But on another system I have (Asus ROG CROSSHAIR VII HERO MB + > >>> AMD Ryzen 1800X CPU) it works absolutely fine. > >>> > >>> # dmesg | grep ccp > >>> [ 5.399853] ccp 0000:07:00.2: ccp: unable to access the device: you might > >>> be running a broken BIOS. > >>> [ 5.401031] ccp 0000:07:00.2: tee enabled > >>> [ 5.401113] ccp 0000:07:00.2: psp enabled > >> > >> Which system is this output from? > > > > My new system ("cs04") with AMD Ryzen 5 5500GT CPU/APU. > > > >> Can you provide the output from lspci -nn? > > > > ``` > > root@cs04:~# lspci -nn > > 00:00.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne Root Complex [1022:1630] > > 00:00.2 IOMMU [0806]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne IOMMU [1022:1631] > > 00:01.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge [1022:1632] > > 00:02.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge [1022:1632] > > 00:02.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne PCIe GPP Bridge [1022:1634] > > 00:02.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne PCIe GPP Bridge [1022:1634] > > 00:08.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge [1022:1632] > > 00:08.1 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Renoir Internal PCIe GPP Bridge to Bus [1022:1635] > > 00:14.0 SMBus [0c05]: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller [1022:790b] (rev 51) > > 00:14.3 ISA bridge [0601]: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge [1022:790e] (rev 51) > > 00:18.0 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 0 [1022:166a] > > 00:18.1 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 1 [1022:166b] > > 00:18.2 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 2 [1022:166c] > > 00:18.3 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 3 [1022:166d] > > 00:18.4 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 4 [1022:166e] > > 00:18.5 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 5 [1022:166f] > > 00:18.6 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 6 [1022:1670] > > 00:18.7 Host bridge [0600]: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 7 [1022:1671] > > 01:00.0 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset USB 3.1 XHCI Controller [1022:43ee] > > 01:00.1 SATA controller [0106]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset SATA Controller [1022:43eb] > > 01:00.2 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] 500 Series Chipset Switch Upstream Port [1022:43e9] > > 02:00.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea] > > 02:08.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea] > > 02:09.0 PCI bridge [0604]: Advanced Micro Devices, Inc. [AMD] Device [1022:43ea] > > 05:00.0 Ethernet controller [0200]: Intel Corporation Ethernet Controller I225-V [8086:15f3] (rev 03) > > 06:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller PM9A1/PM9A3/980PRO [144d:a80a] > > 07:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Cezanne [Radeon Vega Series / Radeon Vega Mobile Series] [1002:1638] (rev c9) > > 07:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Renoir Radeon High Definition Audio Controller [1002:1637] > > 07:00.2 Encryption controller [1080]: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 10h-1fh) Platform Security Processor [1022:15df] > > 07:00.3 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne USB 3.1 [1022:1639] > > 07:00.4 USB controller [0c03]: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne USB 3.1 [1022:1639] > > 07:00.6 Audio device [0403]: Advanced Micro Devices, Inc. [AMD] Family 17h/19h HD Audio Controller [1022:15e3] > > ``` > > > > Cheers, > > Diederik > > > >> Thanks, > >> Tom > >> > >>> > >>> Found an article [1] which could be relevant and downloaded and ran the > >>> accompanying test program (written by Jason Donenfeld): > >>> # ./amd-rdrand-bug > >>> Your RDRAND() does not have the AMD bug. > >>> # ./test-rdrand > >>> RDRAND() |993c0 > >>> RDRAND() �697d > >>> ... (more seemingly random numbers) > >>> RDRAND() �58101 > >>> > >>> I tried it with the latest microcode dd 2024-07-10, but that didn't make > >>> a difference. > >>> > >>> So I'd like to know if this may actually be a bug on the kernel side. > >>> > >>> Happy to provide additional information or run tests or try patches. > >>> > >>> Cheers, > >>> Diederik > >>> > >>> [1] https://arstechnica.com/gadgets/2019/10/how-a-months-old-amd-microcode-bug-destroyed-my-weekend/ > >
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