From 9263abc7fd5d753dbf4cd4bf994bcf9c8c999918 Mon Sep 17 00:00:00 2001 From: Roman Kisel Date: Wed, 8 Jan 2025 14:21:36 -0800 Subject: [PATCH] hyperv: Enable the hypercall output page for the VTL mode Due to the hypercall page not being allocated in the VTL mode, the code resorts to using a part of the input page. Allocate the hypercall output page in the VTL mode thus enabling it to use it for output and share code with dom0. Signed-off-by: Roman Kisel Reviewed-by: Nuno Das Neves Link: https://lore.kernel.org/r/20250108222138.1623703-4-romank@linux.microsoft.com Signed-off-by: Wei Liu Message-ID: <20250108222138.1623703-4-romank@linux.microsoft.com> --- drivers/hv/hv_common.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c index c6ed3ba4bf61..af5d1dc451f6 100644 --- a/drivers/hv/hv_common.c +++ b/drivers/hv/hv_common.c @@ -278,6 +278,11 @@ static void hv_kmsg_dump_register(void) } } +static inline bool hv_output_page_exists(void) +{ + return hv_root_partition || IS_ENABLED(CONFIG_HYPERV_VTL_MODE); +} + int __init hv_common_init(void) { int i; @@ -340,7 +345,7 @@ int __init hv_common_init(void) BUG_ON(!hyperv_pcpu_input_arg); /* Allocate the per-CPU state for output arg for root */ - if (hv_root_partition) { + if (hv_output_page_exists()) { hyperv_pcpu_output_arg = alloc_percpu(void *); BUG_ON(!hyperv_pcpu_output_arg); } @@ -435,7 +440,7 @@ int hv_common_cpu_init(unsigned int cpu) void **inputarg, **outputarg; u64 msr_vp_index; gfp_t flags; - int pgcount = hv_root_partition ? 2 : 1; + const int pgcount = hv_output_page_exists() ? 2 : 1; void *mem; int ret; @@ -453,7 +458,7 @@ int hv_common_cpu_init(unsigned int cpu) if (!mem) return -ENOMEM; - if (hv_root_partition) { + if (hv_output_page_exists()) { outputarg = (void **)this_cpu_ptr(hyperv_pcpu_output_arg); *outputarg = (char *)mem + HV_HYP_PAGE_SIZE; }