2018-01-20 8:03 GMT+01:00 Laura Abbott <labb...@redhat.com>: > On 01/19/2018 10:57 PM, Laura Abbott wrote: >> >> On 01/19/2018 10:15 PM, Tom Lendacky wrote: >>> >>> On 1/19/2018 11:25 PM, Gabriel C wrote: >>>> >>>> 2018-01-20 5:02 GMT+01:00 Laura Abbott <labb...@redhat.com>: >>>>> >>>>> On 01/19/2018 06:23 PM, Gabriel C wrote: >>>>>> >>>>>> >>>>>> 2018-01-20 2:23 GMT+01:00 Laura Abbott <labb...@redhat.com>: >>>>>>> >>>>>>> >>>>>>> Hi, >>>>>> >>>>>> >>>>>> >>>>>> Hi , >>>>>> >>>>>>> >>>>>>> Fedora got multiple reports of an early bootup crash post -rc8. >>>>>>> Bisection showed bacf6b499e11 ("x86/mm: Use a struct to reduce >>>>>>> parameters for SME PGD mapping") . It doesn't revert cleanly >>>>>>> but if I revert the few other changes in arch/x86/mm/mem_encrypt.c >>>>>>> as well it boots up fine. >>>>>>> >>>>>>> Annoyingly, I can't seem to get any actual kernel logs even with >>>>>>> earlyprintk. It just reboots immediately (triple fault?). This >>>>>>> happens on both of my Lenovo machines and I can ask other reporters >>>>>>> for details as well. >>>>>>> >>>>>> >>>>>> I tested these patches on 2 Lenovo Ideapad both with Skylake CPUs >>>>>> on a older dual Xeon box , on 2 Toshibas with AMD APUs , on a RYZEN >>>>>> box , >>>>>> on dual EPYC box .. ofc on EPYC with mem_encrypt=on on the Intel CPUs >>>>>> disabled. >>>>>> >>>>>> Also tested on top 4.14.13 , 4.14.14 as well on top 4.15.0-rc7 and on >>>>>> current master/rc8++ without to see something like this. >>>>>> >>>>>> Also we pushed these patches on 4.14.13/14 and didn't got any reports >>>>>> about >>>>>> something like this. >>>>>> >>>>>> What Lenovo boxes are these ? maybe I find one to reproduce. >>>>>> >>>>>> >>>>>>> $ git bisect log >>>>>>> # bad: [ec835f8104a21f4d4eeb9d316ee71d2b4a7f00de] Merge tag >>>>>>> 'trace-v4.15-rc4-3' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace >>>>>>> # good: [a8750ddca918032d6349adbf9a4b6555e7db20da] Linux 4.15-rc8 >>>>>>> git bisect start 'origin/master' 'v4.15-rc8' >>>>>>> # bad: [79683f80e4f07dba13cc08d0ebcf5c7b0aa1bf68] Merge tag >>>>>>> 'mmc-v4.15-rc2-3' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc >>>>>>> git bisect bad 79683f80e4f07dba13cc08d0ebcf5c7b0aa1bf68 >>>>>>> # good: [161f72ed6dbe7fb176585091d3b797125d310399] Merge tag >>>>>>> 'mac80211-for-davem-2018-01-15' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211 >>>>>>> git bisect good 161f72ed6dbe7fb176585091d3b797125d310399 >>>>>>> # good: [88dc7fca18001fd883e5ace775afa316b68c8f2c] Merge branch >>>>>>> 'x86-pti-for-linus' of >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip >>>>>>> git bisect good 88dc7fca18001fd883e5ace775afa316b68c8f2c >>>>>>> # bad: [d47924417319e3b6a728c0b690f183e75bc2a702] x86/intel_rdt/cqm: >>>>>>> Prevent >>>>>>> use after free >>>>>>> git bisect bad d47924417319e3b6a728c0b690f183e75bc2a702 >>>>>>> # good: [fc90ccfd286eabb05ec54521367df8663cf0bbbf] Revert "x86/apic: >>>>>>> Remove >>>>>>> init_bsp_APIC()" >>>>>>> git bisect good fc90ccfd286eabb05ec54521367df8663cf0bbbf >>>>>>> # bad: [bacf6b499e11760aef73a3bb5ce4e5eea74a3fd4] x86/mm: Use a >>>>>>> struct to >>>>>>> reduce parameters for SME PGD mapping >>>>>>> git bisect bad bacf6b499e11760aef73a3bb5ce4e5eea74a3fd4 >>>>>>> # good: [1303880179e67c59e801429b7e5d0f6b21137d99] x86/mm: Clean up >>>>>>> register >>>>>>> saving in the __enc_copy() assembly code >>>>>>> git bisect good 1303880179e67c59e801429b7e5d0f6b21137d99 >>>>>>> # first bad commit: [bacf6b499e11760aef73a3bb5ce4e5eea74a3fd4] >>>>>>> x86/mm: >>>>>>> Use a >>>>>>> struct to reduce parameters for SME PGD mapping >>>>>>> >>>>>>> >>>>>>> Configuration is at >>>>>>> >>>>>>> >>>>>>> https://git.kernel.org/pub/scm/linux/kernel/git/jwboyer/fedora.git/commit/?h=rawhide >>>>>>> Note that I do think this is something in the Fedora configuration >>>>>>> because a generic "make defconfig" booted just fine. >>>>>> >>>>>> >>>>>> >>>>>> But maybe some of the Fedora patches ? >>>>>> >>>>>> Can you try an kernel with the config but without any patches ? >>>>>> Or a defconfig and just enable CONFIG_AMD_MEM_ENCRYPT ? >>>>>> >>>>> >>>>> The bisect was a vanilla kernel without Fedora patches. >>>> >>>> >>>> Ok . I did an build ( v4.15-rc8-225-g8dd903d2cf7b ) on my AMD >>>> Workstation ( EPYC CPU ) >>> >>> >>> I've tried multiple config combinations on my EPYC system and have not >>> been able to reproduce this issue and have not had any boot issues with >>> mem_encrypt=on or mem_encrypt=off. I don't have access to a non-AMD box >>> at the moment, but I'm really scratching my head on this one. >>> >>>> with your 64bit config and one on the Ideapad ( Intel i7-6498DU ) .. >>>> I disabled Selinux since I don't use it here and module signing. >>>> >>>> Also with your config my serial setup won't work and the kernel hangs >>>> but mem_encrypt=on/off works just fine. >>> >>> >>> If your using the EPYC serial device and you haven't enabled legacy >>> serial device support (if your BIOS supports that), then you're using >>> it as a platform device. The fedora config has not set the >>> CONFIG_X86_AMD_PLATFORM_DEVICE setting so you won't get the module >>> to load and give you serial output. >>> >>> I'm confused when you say the kernel hangs but mem_encrypt=on/off works >>> just fine, can you explain that a bit more? >>> >>>> >>>> Also I notice on the Workstation it takes forever to boot untill >>>> 'DMA-API' reports out-of-memory >>>> ( dunno how much memory it need but the box has 128GB of RAM ).. >>> >>> >> >> The machines I have are a Lenovo X1 Carbon and a Lenovo T470s. >> A Lenovo X220 ThinkPad also reported the problem. >> >> If I comment out sme_encrypt_kernel it boots: >> >> diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c >> index 7ba5d819ebe3..443ef5d3f1fa 100644 >> --- a/arch/x86/kernel/head64.c >> +++ b/arch/x86/kernel/head64.c >> @@ -158,7 +158,7 @@ unsigned long __head __startup_64(unsigned long >> physaddr, >> *p += load_delta - sme_get_me_mask(); >> >> /* Encrypt the kernel and related (if SME is active) */ >> - sme_encrypt_kernel(bp); >> + //sme_encrypt_kernel(bp); >> >> /* >> * Return the SME encryption mask (if SME is active) to be used >> as a >> >> >> Interestingly, I tried to print the values in sme_active >> (sme_me_mask , sev_enabled) followed by a return at the >> very start of sme_encrypt_kernel and that rebooted as well, >> vs booting if I just kept the return. sme_me_mask and >> sev_enabled are explicitly marked as being in .data, >> is it possible they are ending up in a section that isn't >> yet mapped or did I hit print too early? >> >> Thanks, >> Laura >> > > One last note: This was built with gcc 7.2.1
With retpoline patches ( if so what patchset ) ? or the one from gcc7 branch ? I didn't tested with this gcc version , I've tested with gcc6 and gcc8-retpoline-enabled compiler. Regards, Gabriel