Commit 2748566d authored by Cedric Xing's avatar Cedric Xing Committed by Dan Williams
Browse files

x86/tdx: tdx_mcall_get_report0: Return -EBUSY on TDCALL_OPERAND_BUSY error 



Return `-EBUSY` from tdx_mcall_get_report0() when `TDG.MR.REPORT` returns
`TDCALL_OPERAND_BUSY`. This enables the caller to retry obtaining a
TDREPORT later if another VCPU is extending an RTMR concurrently.

Signed-off-by: default avatarCedric Xing <cedric.xing@intel.com>
Acked-by: default avatarDionna Amalie Glaze <dionnaglaze@google.com>
Acked-by: default avatarDave Hansen <dave.hansen@linux.intel.com>
Link: https://patch.msgid.link/20250506-tdx-rtmr-v6-4-ac6ff5e9d58a@intel.com


Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 3f88ca96

arch/x86/coco/tdx/tdx.c

+8 −5
Original line number Diff line number Diff line
@@ -110,12 +110,13 @@ static inline u64 tdg_vm_wr(u64 field, u64 value, u64 mask) 
 *              REPORTDATA to be included into TDREPORT.

 * @tdreport: Address of the output buffer to store TDREPORT.

 *

 * Refer to section titled "TDG.MR.REPORT leaf" in the TDX Module

 * v1.0 specification for more information on TDG.MR.REPORT TDCALL.

 * Refer to section titled "TDG.MR.REPORT leaf" in the TDX Module v1.0

 * specification for more information on TDG.MR.REPORT TDCALL.

 *

 * It is used in the TDX guest driver module to get the TDREPORT0.

 *

 * Return 0 on success, -EINVAL for invalid operands, or -EIO on

 * other TDCALL failures.

 * Return 0 on success, -ENXIO for invalid operands, -EBUSY for busy operation,

 * or -EIO on other TDCALL failures.

 */

int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport)

{
@@ -129,7 +130,9 @@ int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport) 
	ret = __tdcall(TDG_MR_REPORT, &args);

	if (ret) {

		if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND)

			return -EINVAL;

			return -ENXIO;

		else if (TDCALL_RETURN_CODE(ret) == TDCALL_OPERAND_BUSY)

			return -EBUSY;

		return -EIO;

	}