Re: [PATCHv12 4/9] x86/boot/compressed: Handle unaccepted memory

[Kirill A. Shutemov]

On Fri, May 19, 2023 at 02:14:29AM +0300, Kirill A. Shutemov wrote:
> diff --git a/arch/x86/boot/compressed/mem.c b/arch/x86/boot/compressed/mem.c
> index 67594fcb11d9..87372b96d613 100644
> --- a/arch/x86/boot/compressed/mem.c
> +++ b/arch/x86/boot/compressed/mem.c
> @@ -1,9 +1,32 @@
>  // SPDX-License-Identifier: GPL-2.0-only
>  
>  #include "error.h"
> +#include "misc.h"
>  
>  void arch_accept_memory(phys_addr_t start, phys_addr_t end)
>  {
>  	/* Platform-specific memory-acceptance call goes here */
>  	error("Cannot accept memory");
>  }
> +
> +void init_unaccepted_memory(void)
> +{
> +	guid_t guid =  LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID;
> +	struct efi_unaccepted_memory *unaccepted_table;
> +	unsigned long cfg_table_pa;
> +	unsigned int cfg_table_len;
> +	int ret;
> +
> +	ret = efi_get_conf_table(boot_params, &cfg_table_pa, &cfg_table_len);
> +	if (ret)
> +		error("EFI config table not found.");
> +
> +	unaccepted_table = (void *)efi_find_vendor_table(boot_params,
> +							 cfg_table_pa,
> +							 cfg_table_len,
> +							 guid);
> +	if (unaccepted_table->version != 1)
> +		error("Unknown version of unaccepted memory table\n");
> +
> +	set_unaccepted_table(unaccepted_table);
> +}

0-day reported boot failure outdise TDX guest with CONFIG_INTEL_TDX_GUEST=y.

The fixup:

diff --git a/arch/x86/boot/compressed/mem.c b/arch/x86/boot/compressed/mem.c
index 0108c97399a5..8df3d988ae69 100644
--- a/arch/x86/boot/compressed/mem.c
+++ b/arch/x86/boot/compressed/mem.c
@@ -56,6 +56,9 @@ void init_unaccepted_memory(void)
 							 cfg_table_pa,
 							 cfg_table_len,
 							 guid);
+	if (!unaccepted_table)
+		return;
+
 	if (unaccepted_table->version != 1)
 		error("Unknown version of unaccepted memory table\n");
 
-- 
  Kiryl Shutsemau / Kirill A. Shutemov