Re: [Xen-devel] [PATCH v2 2/4] x86/xen: add basic KASAN support for PV kernel
On 17/01/2020 14:56, Boris Ostrovsky wrote: > > > On 1/17/20 7:58 AM, Sergey Dyasli wrote: >> --- a/arch/x86/mm/kasan_init_64.c >> +++ b/arch/x86/mm/kasan_init_64.c >> @@ -13,6 +13,9 @@ >> #include >> #include >> +#include >> +#include >> + >> #include >> #include >> #include >> @@ -332,6 +335,11 @@ void __init kasan_early_init(void) >> for (i = 0; pgtable_l5_enabled() && i < PTRS_PER_P4D; i++) >> kasan_early_shadow_p4d[i] = __p4d(p4d_val); >> +if (xen_pv_domain()) { >> +pgd_t *pv_top_pgt = xen_pv_kasan_early_init(); >> +kasan_map_early_shadow(pv_top_pgt); >> +} >> + > > > I'd suggest replacing this with xen_kasan_early_init() and doing everything, > including PV check, there. This way non-Xen code won't need to be aware of > Xen-specific details such as guest types. This would require exporting kasan_map_early_shadow() via kasan.h. I'm fine with either approach. >> kasan_map_early_shadow(early_top_pgt); >> kasan_map_early_shadow(init_top_pgt); >> } >> @@ -369,6 +377,8 @@ void __init kasan_init(void) >> __pgd(__pa(tmp_p4d_table) | _KERNPG_TABLE)); >> } >> +xen_pv_kasan_pin_pgd(early_top_pgt); >> + > > And drop "_pv" here (and below) for the same reason. This is a reasonable suggestion. >> load_cr3(early_top_pgt); >> __flush_tlb_all(); >> @@ -433,6 +443,8 @@ void __init kasan_init(void) >> load_cr3(init_top_pgt); >> __flush_tlb_all(); >> +xen_pv_kasan_unpin_pgd(early_top_pgt); >> + >> -- Thanks, Sergey ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH v2 2/4] x86/xen: add basic KASAN support for PV kernel
Hi Sergey, Thank you for the patch! Yet something to improve: [auto build test ERROR on xen-tip/linux-next] [also build test ERROR on tip/x86/mm tip/auto-latest linux/master linus/master v5.5-rc7 next-20200121] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Sergey-Dyasli/basic-KASAN-support-for-Xen-PV-domains/20200118-073544 base: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next config: x86_64-randconfig-a002-20200121 (attached as .config) compiler: gcc-6 (Debian 6.3.0-18+deb9u1) 6.3.0 20170516 reproduce: # save the attached .config to linux build tree make ARCH=x86_64 If you fix the issue, kindly add following tag Reported-by: kbuild test robot All errors (new ones prefixed by >>): arch/x86/xen/mmu_pv.c: In function 'xen_pv_kasan_early_init': >> arch/x86/xen/mmu_pv.c:1778:16: error: 'kasan_early_shadow_pud' undeclared >> (first use in this function) set_page_prot(kasan_early_shadow_pud, PAGE_KERNEL_RO); ^~ arch/x86/xen/mmu_pv.c:1778:16: note: each undeclared identifier is reported only once for each function it appears in >> arch/x86/xen/mmu_pv.c:1779:16: error: 'kasan_early_shadow_pmd' undeclared >> (first use in this function) set_page_prot(kasan_early_shadow_pmd, PAGE_KERNEL_RO); ^~ >> arch/x86/xen/mmu_pv.c:1780:16: error: 'kasan_early_shadow_pte' undeclared >> (first use in this function) set_page_prot(kasan_early_shadow_pte, PAGE_KERNEL_RO); ^~ vim +/kasan_early_shadow_pud +1778 arch/x86/xen/mmu_pv.c 1774 1775 pgd_t * __init xen_pv_kasan_early_init(void) 1776 { 1777 /* PV page tables must be read-only */ > 1778 set_page_prot(kasan_early_shadow_pud, PAGE_KERNEL_RO); > 1779 set_page_prot(kasan_early_shadow_pmd, PAGE_KERNEL_RO); > 1780 set_page_prot(kasan_early_shadow_pte, PAGE_KERNEL_RO); 1781 1782 /* Return a pointer to the initial PV page tables */ 1783 return (pgd_t *)xen_start_info->pt_base; 1784 } 1785 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org Intel Corporation .config.gz Description: application/gzip ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH v2 2/4] x86/xen: add basic KASAN support for PV kernel
Hi Sergey, Thank you for the patch! Yet something to improve: [auto build test ERROR on xen-tip/linux-next] [also build test ERROR on tip/x86/mm tip/auto-latest linux/master linus/master v5.5-rc7 next-20200117] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Sergey-Dyasli/basic-KASAN-support-for-Xen-PV-domains/20200118-073544 base: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next config: i386-randconfig-f003-20200120 (attached as .config) compiler: gcc-7 (Debian 7.5.0-3) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag Reported-by: kbuild test robot All errors (new ones prefixed by >>): arch/x86//xen/mmu_pv.c: In function 'xen_pv_kasan_early_init': >> arch/x86//xen/mmu_pv.c:1778:16: error: 'kasan_early_shadow_pud' undeclared >> (first use in this function); did you mean 'kasan_free_shadow'? set_page_prot(kasan_early_shadow_pud, PAGE_KERNEL_RO); ^~ kasan_free_shadow arch/x86//xen/mmu_pv.c:1778:16: note: each undeclared identifier is reported only once for each function it appears in >> arch/x86//xen/mmu_pv.c:1779:16: error: 'kasan_early_shadow_pmd' undeclared >> (first use in this function); did you mean 'kasan_early_shadow_pud'? set_page_prot(kasan_early_shadow_pmd, PAGE_KERNEL_RO); ^~ kasan_early_shadow_pud >> arch/x86//xen/mmu_pv.c:1780:16: error: 'kasan_early_shadow_pte' undeclared >> (first use in this function); did you mean 'kasan_early_shadow_pmd'? set_page_prot(kasan_early_shadow_pte, PAGE_KERNEL_RO); ^~ kasan_early_shadow_pmd vim +1778 arch/x86//xen/mmu_pv.c 1774 1775 pgd_t * __init xen_pv_kasan_early_init(void) 1776 { 1777 /* PV page tables must be read-only */ > 1778 set_page_prot(kasan_early_shadow_pud, PAGE_KERNEL_RO); > 1779 set_page_prot(kasan_early_shadow_pmd, PAGE_KERNEL_RO); > 1780 set_page_prot(kasan_early_shadow_pte, PAGE_KERNEL_RO); 1781 1782 /* Return a pointer to the initial PV page tables */ 1783 return (pgd_t *)xen_start_info->pt_base; 1784 } 1785 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org Intel Corporation .config.gz Description: application/gzip ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel
Re: [Xen-devel] [PATCH v2 2/4] x86/xen: add basic KASAN support for PV kernel
On 1/17/20 7:58 AM, Sergey Dyasli wrote: --- a/arch/x86/mm/kasan_init_64.c +++ b/arch/x86/mm/kasan_init_64.c @@ -13,6 +13,9 @@ #include #include +#include +#include + #include #include #include @@ -332,6 +335,11 @@ void __init kasan_early_init(void) for (i = 0; pgtable_l5_enabled() && i < PTRS_PER_P4D; i++) kasan_early_shadow_p4d[i] = __p4d(p4d_val); + if (xen_pv_domain()) { + pgd_t *pv_top_pgt = xen_pv_kasan_early_init(); + kasan_map_early_shadow(pv_top_pgt); + } + I'd suggest replacing this with xen_kasan_early_init() and doing everything, including PV check, there. This way non-Xen code won't need to be aware of Xen-specific details such as guest types. kasan_map_early_shadow(early_top_pgt); kasan_map_early_shadow(init_top_pgt); } @@ -369,6 +377,8 @@ void __init kasan_init(void) __pgd(__pa(tmp_p4d_table) | _KERNPG_TABLE)); } + xen_pv_kasan_pin_pgd(early_top_pgt); + And drop "_pv" here (and below) for the same reason. -boris load_cr3(early_top_pgt); __flush_tlb_all(); @@ -433,6 +443,8 @@ void __init kasan_init(void) load_cr3(init_top_pgt); __flush_tlb_all(); + xen_pv_kasan_unpin_pgd(early_top_pgt); + ___ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel