diff options
| author | Christophe Leroy <christophe.leroy@csgroup.eu> | 2021-03-04 17:35:09 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2021-03-24 06:09:30 +0300 |
| commit | 90cbac0e995dd92f7bcf82f74aa50250bf194a4a (patch) | |
| tree | 3aed376f4cfed4ced8df36e455819cd5e7279f59 /arch/powerpc/mm | |
| parent | 0b71b37241784c309bea6bd6a9d2027943c4ab94 (diff) | |
| download | linux-90cbac0e995dd92f7bcf82f74aa50250bf194a4a.tar.xz | |
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 <asm/kfence.h>.
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 <christophe.leroy@csgroup.eu>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8dfe1bd2abde26337c1d8c1ad0acfcc82185e0d5.1614868445.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/mm')
| -rw-r--r-- | arch/powerpc/mm/book3s32/mmu.c | 2 | ||||
| -rw-r--r-- | arch/powerpc/mm/fault.c | 7 | ||||
| -rw-r--r-- | arch/powerpc/mm/init_32.c | 3 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_decl.h | 5 | ||||
| -rw-r--r-- | arch/powerpc/mm/nohash/8xx.c | 4 |
5 files changed, 17 insertions, 4 deletions
diff --git a/arch/powerpc/mm/book3s32/mmu.c b/arch/powerpc/mm/book3s32/mmu.c index d7eb266a3f7a..a0db398b5c26 100644 --- a/arch/powerpc/mm/book3s32/mmu.c +++ b/arch/powerpc/mm/book3s32/mmu.c @@ -162,7 +162,7 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) unsigned long border = (unsigned long)__init_begin - PAGE_OFFSET; - if (debug_pagealloc_enabled() || __map_without_bats) { + if (debug_pagealloc_enabled_or_kfence() || __map_without_bats) { pr_debug_once("Read-Write memory mapped without BATs\n"); if (base >= border) return base; 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 <linux/context_tracking.h> #include <linux/hugetlb.h> #include <linux/uaccess.h> +#include <linux/kfence.h> #include <asm/firmware.h> #include <asm/interrupt.h> @@ -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 diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c index 02c7db4087cb..3d690be48e84 100644 --- a/arch/powerpc/mm/init_32.c +++ b/arch/powerpc/mm/init_32.c @@ -97,6 +97,9 @@ static void __init MMU_setup(void) if (IS_ENABLED(CONFIG_PPC_8xx)) return; + if (IS_ENABLED(CONFIG_KFENCE)) + __map_without_ltlbs = 1; + if (debug_pagealloc_enabled()) __map_without_ltlbs = 1; diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h index 998810e68562..7dac910c0b21 100644 --- a/arch/powerpc/mm/mmu_decl.h +++ b/arch/powerpc/mm/mmu_decl.h @@ -185,3 +185,8 @@ void ptdump_check_wx(void); #else static inline void ptdump_check_wx(void) { } #endif + +static inline bool debug_pagealloc_enabled_or_kfence(void) +{ + return IS_ENABLED(CONFIG_KFENCE) || debug_pagealloc_enabled(); +} diff --git a/arch/powerpc/mm/nohash/8xx.c b/arch/powerpc/mm/nohash/8xx.c index 19a3eec1d8c5..71bfdbedacee 100644 --- a/arch/powerpc/mm/nohash/8xx.c +++ b/arch/powerpc/mm/nohash/8xx.c @@ -149,7 +149,7 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) { unsigned long etext8 = ALIGN(__pa(_etext), SZ_8M); unsigned long sinittext = __pa(_sinittext); - bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled(); + bool strict_boundary = strict_kernel_rwx_enabled() || debug_pagealloc_enabled_or_kfence(); unsigned long boundary = strict_boundary ? sinittext : etext8; unsigned long einittext8 = ALIGN(__pa(_einittext), SZ_8M); @@ -161,7 +161,7 @@ unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top) return 0; mmu_mapin_ram_chunk(0, boundary, PAGE_KERNEL_TEXT, true); - if (debug_pagealloc_enabled()) { + if (debug_pagealloc_enabled_or_kfence()) { top = boundary; } else { mmu_mapin_ram_chunk(boundary, einittext8, PAGE_KERNEL_TEXT, true); |