From 12564485ed8caac3c18572793ec01330792c7191 Mon Sep 17 00:00:00 2001 From: Shawn Anastasio Date: Fri, 21 Aug 2020 13:55:56 -0500 Subject: Revert "powerpc/64s: Remove PROT_SAO support" This reverts commit 5c9fa16e8abd342ce04dc830c1ebb2a03abf6c05. Since PROT_SAO can still be useful for certain classes of software, reintroduce it. Concerns about guest migration for LPARs using SAO will be addressed next. Signed-off-by: Shawn Anastasio Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200821185558.35561-2-shawn@anastas.io --- arch/powerpc/include/asm/mman.h | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) (limited to 'arch/powerpc/include/asm/mman.h') diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h index 7c07728af300..4ba303ea27f5 100644 --- a/arch/powerpc/include/asm/mman.h +++ b/arch/powerpc/include/asm/mman.h @@ -13,20 +13,38 @@ #include #include -#ifdef CONFIG_PPC_MEM_KEYS static inline unsigned long arch_calc_vm_prot_bits(unsigned long prot, unsigned long pkey) { - return pkey_to_vmflag_bits(pkey); +#ifdef CONFIG_PPC_MEM_KEYS + return (((prot & PROT_SAO) ? VM_SAO : 0) | pkey_to_vmflag_bits(pkey)); +#else + return ((prot & PROT_SAO) ? VM_SAO : 0); +#endif } #define arch_calc_vm_prot_bits(prot, pkey) arch_calc_vm_prot_bits(prot, pkey) static inline pgprot_t arch_vm_get_page_prot(unsigned long vm_flags) { - return __pgprot(vmflag_to_pte_pkey_bits(vm_flags)); +#ifdef CONFIG_PPC_MEM_KEYS + return (vm_flags & VM_SAO) ? + __pgprot(_PAGE_SAO | vmflag_to_pte_pkey_bits(vm_flags)) : + __pgprot(0 | vmflag_to_pte_pkey_bits(vm_flags)); +#else + return (vm_flags & VM_SAO) ? __pgprot(_PAGE_SAO) : __pgprot(0); +#endif } #define arch_vm_get_page_prot(vm_flags) arch_vm_get_page_prot(vm_flags) -#endif + +static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) +{ + if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_SAO)) + return false; + if ((prot & PROT_SAO) && !cpu_has_feature(CPU_FTR_SAO)) + return false; + return true; +} +#define arch_validate_prot arch_validate_prot #endif /* CONFIG_PPC64 */ #endif /* _ASM_POWERPC_MMAN_H */ -- cgit v1.2.3 From 9b725a90a8f127802e19466d4e336e701bcea0d2 Mon Sep 17 00:00:00 2001 From: Shawn Anastasio Date: Fri, 21 Aug 2020 13:55:57 -0500 Subject: powerpc/64s: Disallow PROT_SAO in LPARs by default Since migration of guests using SAO to ISA 3.1 hosts may cause issues, disable PROT_SAO in LPARs by default and introduce a new Kconfig option PPC_PROT_SAO_LPAR to allow users to enable it if desired. Signed-off-by: Shawn Anastasio Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200821185558.35561-3-shawn@anastas.io --- arch/powerpc/Kconfig | 12 ++++++++++++ arch/powerpc/include/asm/mman.h | 9 +++++++-- 2 files changed, 19 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/include/asm/mman.h') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 1f48bbfb3ce9..65bed1fdeaad 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -860,6 +860,18 @@ config PPC_SUBPAGE_PROT If unsure, say N here. +config PPC_PROT_SAO_LPAR + bool "Support PROT_SAO mappings in LPARs" + depends on PPC_BOOK3S_64 + help + This option adds support for PROT_SAO mappings from userspace + inside LPARs on supported CPUs. + + This may cause issues when performing guest migration from + a CPU that supports SAO to one that does not. + + If unsure, say N here. + config PPC_COPRO_BASE bool diff --git a/arch/powerpc/include/asm/mman.h b/arch/powerpc/include/asm/mman.h index 4ba303ea27f5..7cb6d18f5cd6 100644 --- a/arch/powerpc/include/asm/mman.h +++ b/arch/powerpc/include/asm/mman.h @@ -40,8 +40,13 @@ static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) { if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC | PROT_SEM | PROT_SAO)) return false; - if ((prot & PROT_SAO) && !cpu_has_feature(CPU_FTR_SAO)) - return false; + if (prot & PROT_SAO) { + if (!cpu_has_feature(CPU_FTR_SAO)) + return false; + if (firmware_has_feature(FW_FEATURE_LPAR) && + !IS_ENABLED(CONFIG_PPC_PROT_SAO_LPAR)) + return false; + } return true; } #define arch_validate_prot arch_validate_prot -- cgit v1.2.3