From 90cbac0e995dd92f7bcf82f74aa50250bf194a4a Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Thu, 4 Mar 2021 14:35:09 +0000 Subject: powerpc: Enable KFENCE for PPC32 Add architecture specific implementation details for KFENCE and enable KFENCE for the ppc32 architecture. In particular, this implements the required interface in . KFENCE requires that attributes for pages from its memory pool can individually be set. Therefore, force the Read/Write linear map to be mapped at page granularity. Signed-off-by: Christophe Leroy Acked-by: Marco Elver Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/8dfe1bd2abde26337c1d8c1ad0acfcc82185e0d5.1614868445.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/fault.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index bb368257b55c..bea13682c909 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -418,8 +419,12 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, * take a page fault to a kernel address or a page fault to a user * address outside of dedicated places */ - if (unlikely(!is_user && bad_kernel_fault(regs, error_code, address, is_write))) + if (unlikely(!is_user && bad_kernel_fault(regs, error_code, address, is_write))) { + if (kfence_handle_page_fault(address, is_write, regs)) + return 0; + return SIGSEGV; + } /* * If we're in an interrupt, have no user context or are running -- cgit From af6f2ce84b2f666762f75f085a7e5d6514743a84 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 12 Mar 2021 12:50:37 +0000 Subject: powerpc/32: Call bad_page_fault() from do_page_fault() Now that non volatile registers are saved at all time, no need to split bad_page_fault() out of do_page_fault(). Remove handle_page_fault() and use do_page_fault() directly. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/cfb95be8863204cc2bf45a22ea44dd1d0dc16b7f.1615552867.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/fault.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index bea13682c909..0d4e4ff77e03 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -557,7 +557,7 @@ static long __do_page_fault(struct pt_regs *regs) if (likely(entry)) { instruction_pointer_set(regs, extable_fixup(entry)); return 0; - } else if (IS_ENABLED(CONFIG_PPC_BOOK3S_64)) { + } else if (!IS_ENABLED(CONFIG_PPC_BOOK3E_64)) { __bad_page_fault(regs, err); return 0; } else { -- cgit From 98c26a72751ecb2ed247cdfd6cb2385f37195707 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 15 Mar 2021 14:52:51 +0000 Subject: powerpc/mm: Remove unneeded #ifdef CONFIG_PPC_MEM_KEYS In fault.c, #ifdef CONFIG_PPC_MEM_KEYS is not needed because all functions are always defined, and arch_vma_access_permitted() always returns true when CONFIG_PPC_MEM_KEYS is not defined so access_pkey_error() will return false so bad_access_pkey() will never be called. Include linux/pkeys.h to get a definition of vma_pkeys() for bad_access_pkey(). Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/8038392f38d81f2ad169347efac29146f553b238.1615819955.git.christophe.leroy@csgroup.eu --- arch/powerpc/mm/fault.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 0d4e4ff77e03..0c0b1c2cfb49 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -33,6 +33,7 @@ #include #include #include +#include #include #include @@ -88,7 +89,6 @@ static noinline int bad_area(struct pt_regs *regs, unsigned long address) return __bad_area(regs, address, SEGV_MAPERR); } -#ifdef CONFIG_PPC_MEM_KEYS static noinline int bad_access_pkey(struct pt_regs *regs, unsigned long address, struct vm_area_struct *vma) { @@ -128,7 +128,6 @@ static noinline int bad_access_pkey(struct pt_regs *regs, unsigned long address, return 0; } -#endif static noinline int bad_access(struct pt_regs *regs, unsigned long address) { @@ -235,7 +234,6 @@ static bool bad_kernel_fault(struct pt_regs *regs, unsigned long error_code, return false; } -#ifdef CONFIG_PPC_MEM_KEYS static bool access_pkey_error(bool is_write, bool is_exec, bool is_pkey, struct vm_area_struct *vma) { @@ -249,7 +247,6 @@ static bool access_pkey_error(bool is_write, bool is_exec, bool is_pkey, return false; } -#endif static bool access_error(bool is_write, bool is_exec, struct vm_area_struct *vma) { @@ -497,11 +494,9 @@ retry: return bad_area(regs, address); } -#ifdef CONFIG_PPC_MEM_KEYS if (unlikely(access_pkey_error(is_write, is_exec, (error_code & DSISR_KEYFAULT), vma))) return bad_access_pkey(regs, address, vma); -#endif /* CONFIG_PPC_MEM_KEYS */ if (unlikely(access_error(is_write, is_exec, vma))) return bad_access(regs, address); -- cgit From d738ee8d56de38c91610741f672ec5c1ffae76fc Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Tue, 16 Mar 2021 20:42:02 +1000 Subject: powerpc/64e/interrupt: handle bad_page_fault in C With non-volatile registers saved on interrupt, bad_page_fault can now be called by do_page_fault. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210316104206.407354-9-npiggin@gmail.com --- arch/powerpc/mm/fault.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 0c0b1c2cfb49..18e588fda43d 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -552,12 +552,9 @@ static long __do_page_fault(struct pt_regs *regs) if (likely(entry)) { instruction_pointer_set(regs, extable_fixup(entry)); return 0; - } else if (!IS_ENABLED(CONFIG_PPC_BOOK3E_64)) { + } else { __bad_page_fault(regs, err); return 0; - } else { - /* 32 and 64e handle the bad page fault in asm */ - return err; } } NOKPROBE_SYMBOL(__do_page_fault); -- cgit From c45ba4f44f6b9c98a5fc1511d8853ad6843c877b Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Tue, 16 Mar 2021 20:42:03 +1000 Subject: powerpc: clean up do_page_fault search_exception_tables + __bad_page_fault can be substituted with bad_page_fault, do_page_fault no longer needs to return a value to asm for any sub-architecture, and __bad_page_fault can be static. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210316104206.407354-10-npiggin@gmail.com --- arch/powerpc/mm/fault.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 18e588fda43d..5227def84b5e 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -539,36 +539,25 @@ retry: } NOKPROBE_SYMBOL(___do_page_fault); -static long __do_page_fault(struct pt_regs *regs) +static __always_inline void __do_page_fault(struct pt_regs *regs) { - const struct exception_table_entry *entry; long err; err = ___do_page_fault(regs, regs->dar, regs->dsisr); - if (likely(!err)) - return err; - - entry = search_exception_tables(regs->nip); - if (likely(entry)) { - instruction_pointer_set(regs, extable_fixup(entry)); - return 0; - } else { - __bad_page_fault(regs, err); - return 0; - } + if (unlikely(err)) + bad_page_fault(regs, err); } -NOKPROBE_SYMBOL(__do_page_fault); -DEFINE_INTERRUPT_HANDLER_RET(do_page_fault) +DEFINE_INTERRUPT_HANDLER(do_page_fault) { - return __do_page_fault(regs); + __do_page_fault(regs); } #ifdef CONFIG_PPC_BOOK3S_64 /* Same as do_page_fault but interrupt entry has already run in do_hash_fault */ -long hash__do_page_fault(struct pt_regs *regs) +void hash__do_page_fault(struct pt_regs *regs) { - return __do_page_fault(regs); + __do_page_fault(regs); } NOKPROBE_SYMBOL(hash__do_page_fault); #endif @@ -578,7 +567,7 @@ NOKPROBE_SYMBOL(hash__do_page_fault); * It is called from the DSI and ISI handlers in head.S and from some * of the procedures in traps.c. */ -void __bad_page_fault(struct pt_regs *regs, int sig) +static void __bad_page_fault(struct pt_regs *regs, int sig) { int is_write = page_fault_is_write(regs->dsisr); -- cgit From 7153d4bf0b373428d0393c001019da4d0483fddb Mon Sep 17 00:00:00 2001 From: Xiongwei Song Date: Wed, 14 Apr 2021 19:00:33 +0800 Subject: powerpc/traps: Enhance readability for trap types Define macros to list ppc interrupt types in interttupt.h, replace the reference of the trap hex values with these macros. Referred the hex numbers in arch/powerpc/kernel/exceptions-64e.S, arch/powerpc/kernel/exceptions-64s.S, arch/powerpc/kernel/head_*.S, arch/powerpc/kernel/head_booke.h and arch/powerpc/include/asm/kvm_asm.h. Signed-off-by: Xiongwei Song [mpe: Resolve conflicts in nmi_disables_ftrace(), fix 40x build] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/1618398033-13025-1-git-send-email-sxwjean@me.com --- arch/powerpc/mm/fault.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/powerpc/mm/fault.c') diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 5227def84b5e..34f641d4a2fe 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -197,7 +197,7 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, static bool bad_kernel_fault(struct pt_regs *regs, unsigned long error_code, unsigned long address, bool is_write) { - int is_exec = TRAP(regs) == 0x400; + int is_exec = TRAP(regs) == INTERRUPT_INST_STORAGE; /* NX faults set DSISR_PROTFAULT on the 8xx, DSISR_NOEXEC_OR_G on others */ if (is_exec && (error_code & (DSISR_NOEXEC_OR_G | DSISR_KEYFAULT | @@ -391,7 +391,7 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, struct vm_area_struct * vma; struct mm_struct *mm = current->mm; unsigned int flags = FAULT_FLAG_DEFAULT; - int is_exec = TRAP(regs) == 0x400; + int is_exec = TRAP(regs) == INTERRUPT_INST_STORAGE; int is_user = user_mode(regs); int is_write = page_fault_is_write(error_code); vm_fault_t fault, major = 0; @@ -574,20 +574,20 @@ static void __bad_page_fault(struct pt_regs *regs, int sig) /* kernel has accessed a bad area */ switch (TRAP(regs)) { - case 0x300: - case 0x380: - case 0xe00: + case INTERRUPT_DATA_STORAGE: + case INTERRUPT_DATA_SEGMENT: + case INTERRUPT_H_DATA_STORAGE: pr_alert("BUG: %s on %s at 0x%08lx\n", regs->dar < PAGE_SIZE ? "Kernel NULL pointer dereference" : "Unable to handle kernel data access", is_write ? "write" : "read", regs->dar); break; - case 0x400: - case 0x480: + case INTERRUPT_INST_STORAGE: + case INTERRUPT_INST_SEGMENT: pr_alert("BUG: Unable to handle kernel instruction fetch%s", regs->nip < PAGE_SIZE ? " (NULL pointer?)\n" : "\n"); break; - case 0x600: + case INTERRUPT_ALIGNMENT: pr_alert("BUG: Unable to handle kernel unaligned access at 0x%08lx\n", regs->dar); break; -- cgit