Messages in this thread | ![/](/images/icornerl.gif) | | Date | Tue, 2 Apr 2024 17:31:09 -0500 | Subject | Re: [PATCH] x86/sev: Apply RMP table fixups for kexec. | From | "Kalra, Ashish" <> |
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On 4/2/2024 5:09 PM, Tom Lendacky wrote: > On 3/12/24 13:47, Ashish Kalra wrote: >> From: Ashish Kalra <ashish.kalra@amd.com> >> >> RMP table start and end physical range may not be aligned to 2MB in >> the e820 tables causing fatal RMP page faults during kexec boot when >> new page allocations are done in the same 2MB page as the RMP table. >> Check if RMP table start and end physical range in e820_table is not >> aligned to 2MB and in that case use e820__range_update() to map this >> range to reserved. >> >> Override e820__memory_setup_default() to check and apply these RMP table >> fixups in e820_table before e820_table is used to setup >> e280_table_firmware and e820_table_kexec. >> >> Fixes: c3b86e61b756 ("x86/cpufeatures: Enable/unmask SEV-SNP CPU >> feature") >> Signed-off-by: Ashish Kalra <ashish.kalra@amd.com> >> --- >> arch/x86/virt/svm/sev.c | 52 +++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 52 insertions(+) >> >> diff --git a/arch/x86/virt/svm/sev.c b/arch/x86/virt/svm/sev.c >> index cffe1157a90a..e0d7584df28f 100644 >> --- a/arch/x86/virt/svm/sev.c >> +++ b/arch/x86/virt/svm/sev.c >> @@ -65,6 +65,8 @@ static u64 probed_rmp_base, probed_rmp_size; >> static struct rmpentry *rmptable __ro_after_init; >> static u64 rmptable_max_pfn __ro_after_init; >> +static char *__init snp_rmptable_e820_fixup(void); >> + >> static LIST_HEAD(snp_leaked_pages_list); >> static DEFINE_SPINLOCK(snp_leaked_pages_list_lock); >> @@ -160,9 +162,59 @@ bool snp_probe_rmptable_info(void) >> pr_info("RMP table physical range [0x%016llx - 0x%016llx]\n", >> probed_rmp_base, probed_rmp_base + probed_rmp_size - 1); >> + /* >> + * Override e820__memory_setup_default() to do any RMP table fixups >> + * for kexec if required. >> + */ >> + x86_init.resources.memory_setup = snp_rmptable_e820_fixup; > > This produces a build warning: > > WARNING: modpost: vmlinux: section mismatch in reference: > snp_probe_rmptable_info+0x95 (section: .text) -> x86_init (section: > .init.data) > WARNING: modpost: vmlinux: section mismatch in reference: > snp_probe_rmptable_info+0x99 (section: .text) -> > snp_rmptable_e820_fixup (section: .init.text) > Oh, so this requires snp_probe_rmptable_info() to be fixed to use the __init macro.
I believe that snp_probe_rmptable_info() should be anyway using the __init macro and this fix for snp_probe_rmptable_info() needs to be sent as a separate patch and regardless of this patch getting merged or not.
Thanks, Ashish
> Thanks, > Tom > >> + >> return true; >> }
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