From: Tianyu Lan <ltykernel@xxxxxxxxx> Sent: Friday, November 18, 2022 7:46 PM > > Hypervisor needs to access iput arg page and guest should decrypt > the page. > > Signed-off-by: Tianyu Lan <tiala@xxxxxxxxxxxxx> > --- > drivers/hv/hv_common.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c > index 2c6602571c47..c16961e686a0 100644 > --- a/drivers/hv/hv_common.c > +++ b/drivers/hv/hv_common.c > @@ -21,6 +21,7 @@ > #include <linux/ptrace.h> > #include <linux/slab.h> > #include <linux/dma-map-ops.h> > +#include <linux/set_memory.h> > #include <asm/hyperv-tlfs.h> > #include <asm/mshyperv.h> > > @@ -125,6 +126,7 @@ int hv_common_cpu_init(unsigned int cpu) > u64 msr_vp_index; > gfp_t flags; > int pgcount = hv_root_partition ? 2 : 1; > + int ret; > > /* hv_cpu_init() can be called with IRQs disabled from hv_resume() */ > flags = irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL; > @@ -134,6 +136,16 @@ int hv_common_cpu_init(unsigned int cpu) > if (!(*inputarg)) > return -ENOMEM; > > + if (hv_isolation_type_en_snp()) { > + ret = set_memory_decrypted((unsigned long)*inputarg, 1); > + if (ret) { > + kfree(*inputarg); After the kfree(), set *inputarg back to NULL. There's other code that tests the value of *inputarg to know if the per-CPU hypercall page has been successfully allocated. > + return ret; > + } > + > + memset(*inputarg, 0x00, PAGE_SIZE); > + } > + > if (hv_root_partition) { > outputarg = (void **)this_cpu_ptr(hyperv_pcpu_output_arg); > *outputarg = (char *)(*inputarg) + HV_HYP_PAGE_SIZE; > @@ -168,6 +180,9 @@ int hv_common_cpu_die(unsigned int cpu) > > local_irq_restore(flags); > > + if (hv_isolation_type_en_snp()) > + set_memory_encrypted((unsigned long)mem, 1); > + > kfree(mem); > > return 0; > -- > 2.25.1