Re: [PATCH] kdump, vmcoreinfo: Export sme_me_mask value to vmcoreinfo

From: Boris Petkov
Date: Fri Oct 26 2018 - 05:43:27 EST

On October 26, 2018 10:36:30 AM GMT+01:00, Lianbo Jiang <lijiang@xxxxxxxxxx> wrote:
>For AMD machine with SME feature, makedumpfile tools need to know
>whether the crash kernel was encrypted or not.


> So it is necessary
>to write the sme_me_mask to vmcoreinfo.
>Signed-off-by: Lianbo Jiang <lijiang@xxxxxxxxxx>
> arch/x86/kernel/machine_kexec_64.c | 2 ++
> 1 file changed, 2 insertions(+)
>diff --git a/arch/x86/kernel/machine_kexec_64.c
>index 4c8acdfdc5a7..dcfdb64d1097 100644
>--- a/arch/x86/kernel/machine_kexec_64.c
>+++ b/arch/x86/kernel/machine_kexec_64.c
>@@ -357,6 +357,8 @@ void arch_crash_save_vmcoreinfo(void)
> vmcoreinfo_append_str("NUMBER(pgtable_l5_enabled)=%d\n",
> pgtable_l5_enabled());
>+ VMCOREINFO_NUMBER(sme_me_mask);

No we're not going to expose a kernel-internal mask to userspace.

If at all needed, add functions to kexec which figure out whether we are encrypted or not and export that result as a kexec variable.

Sent from a small device: formatting sux and brevity is inevitable.