From 6a11f75b6a17b5d9ac5025f8d048382fd1f47377 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Tue, 31 Mar 2009 15:23:17 -0700 Subject: generic debug pagealloc CONFIG_DEBUG_PAGEALLOC is now supported by x86, powerpc, sparc64, and s390. This patch implements it for the rest of the architectures by filling the pages with poison byte patterns after free_pages() and verifying the poison patterns before alloc_pages(). This generic one cannot detect invalid page accesses immediately but invalid read access may cause invalid dereference by poisoned memory and invalid write access can be detected after a long delay. Signed-off-by: Akinobu Mita Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/avr32/mm/fault.c | 18 ------------------ arch/powerpc/Kconfig | 3 +++ arch/powerpc/Kconfig.debug | 1 + arch/s390/Kconfig | 3 +++ arch/s390/Kconfig.debug | 1 + arch/sparc/Kconfig | 3 +++ arch/sparc/Kconfig.debug | 3 ++- arch/x86/Kconfig | 3 +++ arch/x86/Kconfig.debug | 1 + 9 files changed, 17 insertions(+), 19 deletions(-) (limited to 'arch') diff --git a/arch/avr32/mm/fault.c b/arch/avr32/mm/fault.c index ce4e4296b954..62d4abbaa654 100644 --- a/arch/avr32/mm/fault.c +++ b/arch/avr32/mm/fault.c @@ -250,21 +250,3 @@ asmlinkage void do_bus_error(unsigned long addr, int write_access, dump_dtlb(); die("Bus Error", regs, SIGKILL); } - -/* - * This functionality is currently not possible to implement because - * we're using segmentation to ensure a fixed mapping of the kernel - * virtual address space. - * - * It would be possible to implement this, but it would require us to - * disable segmentation at startup and load the kernel mappings into - * the TLB like any other pages. There will be lots of trickery to - * avoid recursive invocation of the TLB miss handler, though... - */ -#ifdef CONFIG_DEBUG_PAGEALLOC -void kernel_map_pages(struct page *page, int numpages, int enable) -{ - -} -EXPORT_SYMBOL(kernel_map_pages); -#endif diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index ad6b1c084fe3..45192dce65c4 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -228,6 +228,9 @@ config PPC_OF_PLATFORM_PCI depends on PPC64 # not supported on 32 bits yet default n +config ARCH_SUPPORTS_DEBUG_PAGEALLOC + def_bool y + source "init/Kconfig" source "kernel/Kconfig.freezer" diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index 22091bbfdc9b..6aa0b5e087cd 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -30,6 +30,7 @@ config DEBUG_STACK_USAGE config DEBUG_PAGEALLOC bool "Debug page memory allocations" depends on DEBUG_KERNEL && !HIBERNATION + depends on ARCH_SUPPORTS_DEBUG_PAGEALLOC help Unmap pages from the kernel linear mapping after free_pages(). This results in a large slowdown, but helps to find certain types diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 2a8af5e16345..dcb667c4375a 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -72,6 +72,9 @@ config PGSTE config VIRT_CPU_ACCOUNTING def_bool y +config ARCH_SUPPORTS_DEBUG_PAGEALLOC + def_bool y + mainmenu "Linux Kernel Configuration" config S390 diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug index 4599fa06bd82..7e297a3cde34 100644 --- a/arch/s390/Kconfig.debug +++ b/arch/s390/Kconfig.debug @@ -9,6 +9,7 @@ source "lib/Kconfig.debug" config DEBUG_PAGEALLOC bool "Debug page memory allocations" depends on DEBUG_KERNEL + depends on ARCH_SUPPORTS_DEBUG_PAGEALLOC help Unmap pages from the kernel linear mapping after free_pages(). This results in a slowdown, but helps to find certain types of diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index c3ea215334f6..cc12cd48bbc5 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -124,6 +124,9 @@ config ARCH_NO_VIRT_TO_BUS config OF def_bool y +config ARCH_SUPPORTS_DEBUG_PAGEALLOC + def_bool y if SPARC64 + source "init/Kconfig" source "kernel/Kconfig.freezer" diff --git a/arch/sparc/Kconfig.debug b/arch/sparc/Kconfig.debug index b8a15e271bfa..d001b42041a5 100644 --- a/arch/sparc/Kconfig.debug +++ b/arch/sparc/Kconfig.debug @@ -24,7 +24,8 @@ config STACK_DEBUG config DEBUG_PAGEALLOC bool "Debug page memory allocations" - depends on SPARC64 && DEBUG_KERNEL && !HIBERNATION + depends on DEBUG_KERNEL && !HIBERNATION + depends on ARCH_SUPPORTS_DEBUG_PAGEALLOC help Unmap pages from the kernel linear mapping after free_pages(). This results in a large slowdown, but helps to find certain types diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 45161b816313..748e50a1a152 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -165,6 +165,9 @@ config AUDIT_ARCH config ARCH_SUPPORTS_OPTIMIZED_INLINING def_bool y +config ARCH_SUPPORTS_DEBUG_PAGEALLOC + def_bool y + # Use the generic interrupt handling code in kernel/irq/: config GENERIC_HARDIRQS bool diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index fdb45df608b6..a345cb5447a8 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -75,6 +75,7 @@ config DEBUG_STACK_USAGE config DEBUG_PAGEALLOC bool "Debug page memory allocations" depends on DEBUG_KERNEL + depends on ARCH_SUPPORTS_DEBUG_PAGEALLOC ---help--- Unmap pages from the kernel linear mapping after free_pages(). This results in a large slowdown, but helps to find certain types -- cgit v1.2.3-59-g8ed1b