| Message ID | 20240819131924.372366-7-steven.price@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: Support for running as a guest in Arm CCA | expand |
On Mon, Aug 19, 2024 at 02:19:11PM +0100, Steven Price wrote: > The top bit of the configured IPA size is used as an attribute to > control whether the address is protected or shared. Query the > configuration from the RMM to assertain which bit this is. > > Co-developed-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Steven Price <steven.price@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
On 8/19/24 11:19 PM, Steven Price wrote: > The top bit of the configured IPA size is used as an attribute to > control whether the address is protected or shared. Query the > configuration from the RMM to assertain which bit this is. > > Co-developed-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> > Signed-off-by: Steven Price <steven.price@arm.com> > --- > Changes since v4: > * Make PROT_NS_SHARED check is_realm_world() to reduce impact on > non-CCA systems. > Changes since v2: > * Drop unneeded extra brackets from PROT_NS_SHARED. > * Drop the explicit alignment from 'config' as struct realm_config now > specifies the alignment. > --- > arch/arm64/include/asm/pgtable-prot.h | 4 ++++ > arch/arm64/kernel/rsi.c | 8 ++++++++ > 2 files changed, 12 insertions(+) > One nit below. Reviewed-by: Gavin Shan <gshan@redhat.com> > diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h > index b11cfb9fdd37..5e578274a3b7 100644 > --- a/arch/arm64/include/asm/pgtable-prot.h > +++ b/arch/arm64/include/asm/pgtable-prot.h > @@ -68,8 +68,12 @@ > > #include <asm/cpufeature.h> > #include <asm/pgtable-types.h> > +#include <asm/rsi.h> > > extern bool arm64_use_ng_mappings; > +extern unsigned long prot_ns_shared; > + > +#define PROT_NS_SHARED (is_realm_world() ? prot_ns_shared : 0) > > #define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0) > #define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0) > diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c > index 128a9a05a96b..e968a5c9929e 100644 > --- a/arch/arm64/kernel/rsi.c > +++ b/arch/arm64/kernel/rsi.c > @@ -8,6 +8,11 @@ > #include <linux/psci.h> > #include <asm/rsi.h> > > +struct realm_config config; > + > +unsigned long prot_ns_shared; > +EXPORT_SYMBOL(prot_ns_shared); > + > DEFINE_STATIC_KEY_FALSE_RO(rsi_present); > EXPORT_SYMBOL(rsi_present); > > @@ -72,6 +77,9 @@ void __init arm64_rsi_init(void) > return; > if (!rsi_version_matches()) > return; > + if (rsi_get_realm_config(&config)) > + return; > + prot_ns_shared = BIT(config.ipa_bits - 1); > > static_branch_enable(&rsi_present); > } Nit: It's probably worthy to warn on errors returned from rsi_get_realm_config(), It's hard to debug and follow if it fails silently. Thanks, Gavin
diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index b11cfb9fdd37..5e578274a3b7 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -68,8 +68,12 @@ #include <asm/cpufeature.h> #include <asm/pgtable-types.h> +#include <asm/rsi.h> extern bool arm64_use_ng_mappings; +extern unsigned long prot_ns_shared; + +#define PROT_NS_SHARED (is_realm_world() ? prot_ns_shared : 0) #define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0) #define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0) diff --git a/arch/arm64/kernel/rsi.c b/arch/arm64/kernel/rsi.c index 128a9a05a96b..e968a5c9929e 100644 --- a/arch/arm64/kernel/rsi.c +++ b/arch/arm64/kernel/rsi.c @@ -8,6 +8,11 @@ #include <linux/psci.h> #include <asm/rsi.h> +struct realm_config config; + +unsigned long prot_ns_shared; +EXPORT_SYMBOL(prot_ns_shared); + DEFINE_STATIC_KEY_FALSE_RO(rsi_present); EXPORT_SYMBOL(rsi_present); @@ -72,6 +77,9 @@ void __init arm64_rsi_init(void) return; if (!rsi_version_matches()) return; + if (rsi_get_realm_config(&config)) + return; + prot_ns_shared = BIT(config.ipa_bits - 1); static_branch_enable(&rsi_present); }