From: "Borislav Petkov (AMD)" <[email protected]>
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) <[email protected]>
---
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
config CRYPTO_DEV_SP_PSP
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
help
Provide support for the AMD Platform Security Processor (PSP).
The PSP is a dedicated processor that provides support for key
--
2.43.0
On 2/7/24 14:47, Borislav Petkov wrote:
> From: "Borislav Petkov (AMD)" <[email protected]>
>
> 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) <[email protected]>
> ---
> 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
> config CRYPTO_DEV_SP_PSP
> 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:
#ifdef CONFIG_AMD_IOMMU
extern bool amd_iommu_snp_en;
#else
#define amd_iommu_snp_en false
#endif
I think this would be better in case these should be referenced elsewhere
in the future.
Thanks,
Tom
> help
> Provide support for the AMD Platform Security Processor (PSP).
> The PSP is a dedicated processor that provides support for key
On Fri, Feb 09, 2024 at 11:51:37AM -0600, Tom Lendacky wrote:
> 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)
Pretty much, except the thunk should say that it is the thunk that gets
called:
#if defined(CONFIG_AMD_IOMMU) && defined(CONFIG_KVM_AMD_SEV)
int amd_iommu_snp_disable(void);
#else
static inline int amd_iommu_snp_disable(void) { return -ENODEV; }
#endif
and return -ENODEV to denote that so that the caller doesn't wonder
what's going on.
> I think this would be better in case these should be referenced
> elsewhere in the future.
However, looking at all that code, its design still looks iffy to me.
iommu_page_make_shared() and amd_iommu_snp_disable() is functionality
which the *IOMMU* provides in order to deal with SEV* guests. So that
functionality should be behind
CONFIG_AMD_IOMMU_SEV
or so, on which all its users depend or select. I'd prefer depend tho.
Putting IOMMU facilities around a KVM Kconfig symbol CONFIG_KVM_AMD_SEV
is simply bad design. There are providers of functionality which is
behind Kconfig symbols and users which depend on those. The current
thing is a hack IMNSVHO.
Thx.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
The following commit has been merged into the x86/sev branch of tip:
Commit-ID: ee8ff8768735edc3e013837c4416f819543ddc17
Gitweb: https://git.kernel.org/tip/ee8ff8768735edc3e013837c4416f819543ddc17
Author: Borislav Petkov (AMD) <[email protected]>
AuthorDate: Wed, 07 Feb 2024 21:47:21 +01:00
Committer: Borislav Petkov (AMD) <[email protected]>
CommitterDate: Tue, 13 Feb 2024 12:21:15 +01:00
crypto: ccp - Have it depend on AMD_IOMMU
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) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
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 32268e2..f394e45 100644
--- a/drivers/crypto/ccp/Kconfig
+++ b/drivers/crypto/ccp/Kconfig
@@ -38,7 +38,7 @@ config CRYPTO_DEV_CCP_CRYPTO
config CRYPTO_DEV_SP_PSP
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
help
Provide support for the AMD Platform Security Processor (PSP).
The PSP is a dedicated processor that provides support for key