From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: [PATCH 27/29] x86/mm: Report which part of kernel image is freed Date: Thu, 26 Sep 2019 10:56:00 -0700 Message-ID: <20190926175602.33098-28-keescook@chromium.org> References: <20190926175602.33098-1-keescook@chromium.org> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=lMtAqLKIV7iaSMLHYcvPv+kohztZyY/Z+5xJ+D8O728=; b=UFt+V8/BMr/oQ/8CSnatqgIyXSDcvs3/19JyozsCgFPsqS0v3M/8jZg1fzL6Qc1wTN zcaktCKmkfBZrskzRVnW1lpnKnbT1CTtX0kHIF9idT+XJVt92g3bq0Dpz4OLE6nMC5XH NW8BhxFynv4qPmoQ9WfuzroS1lPcxOvqA3Vq0= In-Reply-To: <20190926175602.33098-1-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Thomas Gleixner Cc: Kees Cook , Rick Edgecombe , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Dave Hansen , Andy Lutomirski , Arnd Bergmann , linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-alpha@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-c6x-dev@linux-c6x.org, Yoshinori Sato , Michal Simek , linux-parisc@vger.kernel.org, linux-xtensa@linux-xtensa.org, x86@kernel.org, linux-kernel@vger.kernel.org The memory freeing report wasn't very useful for figuring out which parts of the kernel image were being freed. This adds the details for clearer reporting. Before: [ 2.150450] Freeing unused kernel image memory: 1348K [ 2.154574] Write protecting the kernel read-only data: 20480k [ 2.157641] Freeing unused kernel image memory: 2040K [ 2.158827] Freeing unused kernel image memory: 172K After: [ 2.329678] Freeing unused kernel image (initmem) memory: 1348K [ 2.331953] Write protecting the kernel read-only data: 20480k [ 2.335361] Freeing unused kernel image (text/rodata gap) memory: 2040K [ 2.336927] Freeing unused kernel image (rodata/data gap) memory: 172K Signed-off-by: Kees Cook --- arch/x86/include/asm/processor.h | 2 +- arch/x86/mm/init.c | 8 ++++---- arch/x86/mm/init_64.c | 6 ++++-- 3 files changed, 9 insertions(+), 7 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 6e0a3b43d027..790f250d39a8 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -958,7 +958,7 @@ static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) extern unsigned long arch_align_stack(unsigned long sp); void free_init_pages(const char *what, unsigned long begin, unsigned long end); -extern void free_kernel_image_pages(void *begin, void *end); +extern void free_kernel_image_pages(const char *what, void *begin, void *end); void default_idle(void); #ifdef CONFIG_XEN diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index fd10d91a6115..e7bb483557c9 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -829,14 +829,13 @@ void free_init_pages(const char *what, unsigned long begin, unsigned long end) * used for the kernel image only. free_init_pages() will do the * right thing for either kind of address. */ -void free_kernel_image_pages(void *begin, void *end) +void free_kernel_image_pages(const char *what, void *begin, void *end) { unsigned long begin_ul = (unsigned long)begin; unsigned long end_ul = (unsigned long)end; unsigned long len_pages = (end_ul - begin_ul) >> PAGE_SHIFT; - - free_init_pages("unused kernel image", begin_ul, end_ul); + free_init_pages(what, begin_ul, end_ul); /* * PTI maps some of the kernel into userspace. For performance, @@ -865,7 +864,8 @@ void __ref free_initmem(void) mem_encrypt_free_decrypted_mem(); - free_kernel_image_pages(&__init_begin, &__init_end); + free_kernel_image_pages("unused kernel image (initmem)", + &__init_begin, &__init_end); } #ifdef CONFIG_BLK_DEV_INITRD diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index e67ddca8b7a8..dcb9bc961b39 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1334,8 +1334,10 @@ void mark_rodata_ro(void) set_memory_ro(start, (end-start) >> PAGE_SHIFT); #endif - free_kernel_image_pages((void *)text_end, (void *)rodata_start); - free_kernel_image_pages((void *)rodata_end, (void *)_sdata); + free_kernel_image_pages("unused kernel image (text/rodata gap)", + (void *)text_end, (void *)rodata_start); + free_kernel_image_pages("unused kernel image (rodata/data gap)", + (void *)rodata_end, (void *)_sdata); debug_checkwx(); } -- 2.17.1