From: Borislav Petkov (AMD) <bp@xxxxxxxxx> commit fa4ae42cc60a7dea30e8f2db444b808d80862345 upstream. snp_issue_guest_request() checks the value returned by the hypervisor in sw_exit_info_2 and returns a different error depending on it. Convert those checks into a switch-case to make it more readable when more error values are going to be checked in the future. No functional changes. Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Link: https://lore.kernel.org/r/20230307192449.24732-8-bp@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/sev.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) --- a/arch/x86/kernel/sev.c +++ b/arch/x86/kernel/sev.c @@ -2210,15 +2210,21 @@ int snp_issue_guest_request(u64 exit_cod goto e_put; *fw_err = ghcb->save.sw_exit_info_2; - if (ghcb->save.sw_exit_info_2) { + switch (*fw_err) { + case 0: + break; + + case SNP_GUEST_REQ_INVALID_LEN: /* Number of expected pages are returned in RBX */ - if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST && - ghcb->save.sw_exit_info_2 == SNP_GUEST_REQ_INVALID_LEN) { + if (exit_code == SVM_VMGEXIT_EXT_GUEST_REQUEST) { input->data_npages = ghcb_get_rbx(ghcb); ret = -ENOSPC; - } else { - ret = -EIO; + break; } + fallthrough; + default: + ret = -EIO; + break; } e_put:
