Re: [PATCH] crypto: ccp - Have it depend on AMD_IOMMU

From: Tom Lendacky
Date: Fri Feb 09 2024 - 12:51:54 EST

On 2/7/24 14:47, Borislav Petkov wrote:
From: "Borislav Petkov (AMD)" <bp@xxxxxxxxx>

sev-dev.c calls code in the AMD IOMMU now but that can't really work if
latter is not enabled in Kconfig:

ld: vmlinux.o: in function `__sev_firmware_shutdown.isra.0':
sev-dev.c:(.text+0x2501f0e): undefined reference to `amd_iommu_snp_disable'
ld: vmlinux.o: in function `snp_rmptable_init':
sev.c:(.init.text+0x26260): undefined reference to `amd_iommu_snp_en'
make[2]: *** [scripts/Makefile.vmlinux:37: vmlinux] Error 1
make: *** [Makefile:240: __sub-make] Error 2

Fix those deps.

Fixes: f366a8dac1b8 ("iommu/amd: Clean up RMP entries for IOMMU pages during SNP shutdown")
Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx>
drivers/crypto/ccp/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/ccp/Kconfig b/drivers/crypto/ccp/Kconfig
index 32268e239bf1..f394e45e11ab 100644
--- a/drivers/crypto/ccp/Kconfig
+++ b/drivers/crypto/ccp/Kconfig
@@ -38,7 +38,7 @@ config CRYPTO_DEV_CCP_CRYPTO
bool "Platform Security Processor (PSP) device"
default y
- depends on CRYPTO_DEV_CCP_DD && X86_64
+ depends on CRYPTO_DEV_CCP_DD && X86_64 && AMD_IOMMU

Or should the ifdef around amd_iommu_snp_disable() in include/linux/amd-iommu.h instead be:

#if defined(CONFIG_AMD_IOMMU) && defined(CONFIG_KVM_AMD_SEV)

and amd_iommu_snp_en be protected in arch/x86/include/asm/iommu.h as:

extern bool amd_iommu_snp_en;
#define amd_iommu_snp_en false

I think this would be better in case these should be referenced elsewhere in the future.


Provide support for the AMD Platform Security Processor (PSP).
The PSP is a dedicated processor that provides support for key