| Message ID | 20230920035336.854212-2-willy@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] mm: Report success more often from filemap_map_folio_range() | expand |
On Wed, Sep 20, 2023 at 04:53:36AM +0100, Matthew Wilcox (Oracle) wrote: > In order to fix the L1TF vulnerability, x86 can invert the PTE bits for > PROT_NONE VMAs, which means we cannot move from one PTE to the next by > adding 1 to the PFN field of the PTE. Abstract advancing the PTE to > the next PFN through a pte_next_pfn() function/macro. Argh, wrong version. New version coming up.
Hi Matthew,
kernel test robot noticed the following build errors:
[auto build test ERROR on akpm-mm/mm-everything]
url: https://github.com/intel-lab-lkp/linux/commits/Matthew-Wilcox-Oracle/mm-Abstract-moving-to-the-next-PFN/20230920-115500
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20230920035336.854212-2-willy%40infradead.org
patch subject: [PATCH 2/2] mm: Abstract moving to the next PFN
config: um-i386_defconfig (https://download.01.org/0day-ci/archive/20230920/202309201731.Tr9SZYEz-lkp@intel.com/config)
compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230920/202309201731.Tr9SZYEz-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309201731.Tr9SZYEz-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from include/linux/mm.h:29:0,
from include/linux/ring_buffer.h:5,
from include/linux/trace_events.h:6,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:90,
from init/main.c:21:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from arch/x86/um/ptrace_32.c:6:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/x86/um/ptrace_32.c: At top level:
arch/x86/um/ptrace_32.c:15:6: warning: no previous declaration for 'arch_switch_to' [-Wmissing-declarations]
void arch_switch_to(struct task_struct *to)
^~~~~~~~~~~~~~
arch/x86/um/ptrace_32.c:28:5: warning: no previous declaration for 'is_syscall' [-Wmissing-declarations]
int is_syscall(unsigned long addr)
^~~~~~~~~~
arch/x86/um/ptrace_32.c:125:5: warning: no previous declaration for 'poke_user' [-Wmissing-declarations]
int poke_user(struct task_struct *child, long addr, long data)
^~~~~~~~~
arch/x86/um/ptrace_32.c:177:5: warning: no previous declaration for 'peek_user' [-Wmissing-declarations]
int peek_user(struct task_struct *child, long addr, long data)
^~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/pid_namespace.h:7,
from include/linux/ptrace.h:10,
from arch/x86/um/signal.c:9:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/x86/um/signal.c: At top level:
arch/x86/um/signal.c:453:6: warning: no previous declaration for 'sys_sigreturn' [-Wmissing-declarations]
long sys_sigreturn(void)
^~~~~~~~~~~~~
arch/x86/um/signal.c:560:6: warning: no previous declaration for 'sys_rt_sigreturn' [-Wmissing-declarations]
long sys_rt_sigreturn(void)
^~~~~~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/ring_buffer.h:5,
from include/linux/trace_events.h:6,
from include/trace/syscall.h:7,
from include/linux/syscalls.h:90,
from arch/x86/um/tls_32.c:8:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/x86/um/tls_32.c: At top level:
arch/x86/um/tls_32.c:23:5: warning: no previous declaration for 'do_set_thread_area' [-Wmissing-declarations]
int do_set_thread_area(struct user_desc *info)
^~~~~~~~~~~~~~~~~~
arch/x86/um/tls_32.c:39:5: warning: no previous declaration for 'do_get_thread_area' [-Wmissing-declarations]
int do_get_thread_area(struct user_desc *info)
^~~~~~~~~~~~~~~~~~
arch/x86/um/tls_32.c:184:5: warning: no previous declaration for 'arch_switch_tls' [-Wmissing-declarations]
int arch_switch_tls(struct task_struct *to)
^~~~~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/coredump.h:6,
from arch/x86/um/elfcore.c:3:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/x86/um/elfcore.c: At top level:
arch/x86/um/elfcore.c:10:12: warning: no previous declaration for 'elf_core_extra_phdrs' [-Wmissing-declarations]
Elf32_Half elf_core_extra_phdrs(struct coredump_params *cprm)
^~~~~~~~~~~~~~~~~~~~
arch/x86/um/elfcore.c:15:5: warning: no previous declaration for 'elf_core_write_extra_phdrs' [-Wmissing-declarations]
int elf_core_write_extra_phdrs(struct coredump_params *cprm, loff_t offset)
^~~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/um/elfcore.c:42:5: warning: no previous declaration for 'elf_core_write_extra_data' [-Wmissing-declarations]
int elf_core_write_extra_data(struct coredump_params *cprm)
^~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/um/elfcore.c:63:8: warning: no previous declaration for 'elf_core_extra_data_size' [-Wmissing-declarations]
size_t elf_core_extra_data_size(struct coredump_params *cprm)
^~~~~~~~~~~~~~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/kallsyms.h:13,
from include/linux/ftrace.h:13,
from include/linux/kprobes.h:28,
from include/linux/kgdb.h:19,
from kernel/panic.c:15:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
kernel/panic.c: In function '__warn':
kernel/panic.c:670:3: warning: function '__warn' might be a candidate for 'gnu_printf' format attribute [-Wsuggest-attribute=format]
vprintk(args->fmt, args->args);
^~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/memblock.h:12,
from arch/um/kernel/mem.c:8:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/um/kernel/mem.c: At top level:
arch/um/kernel/mem.c:202:8: warning: no previous declaration for 'pgd_alloc' [-Wmissing-declarations]
pgd_t *pgd_alloc(struct mm_struct *mm)
^~~~~~~~~
arch/um/kernel/mem.c:215:7: warning: no previous declaration for 'uml_kmalloc' [-Wmissing-declarations]
void *uml_kmalloc(int size, int flags)
^~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from arch/um/kernel/process.c:12:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/um/kernel/process.c: At top level:
arch/um/kernel/process.c:51:5: warning: no previous declaration for 'pid_to_processor_id' [-Wmissing-declarations]
int pid_to_processor_id(int pid)
^~~~~~~~~~~~~~~~~~~
arch/um/kernel/process.c:87:7: warning: no previous declaration for '__switch_to' [-Wmissing-declarations]
void *__switch_to(struct task_struct *from, struct task_struct *to)
^~~~~~~~~~~
arch/um/kernel/process.c: In function 'new_thread_handler':
arch/um/kernel/process.c:122:21: warning: variable 'n' set but not used [-Wunused-but-set-variable]
int (*fn)(void *), n;
^
arch/um/kernel/process.c: At top level:
arch/um/kernel/process.c:140:6: warning: no previous declaration for 'fork_handler' [-Wmissing-declarations]
void fork_handler(void)
^~~~~~~~~~~~
arch/um/kernel/process.c:217:6: warning: no previous declaration for 'arch_cpu_idle' [-Wmissing-declarations]
void arch_cpu_idle(void)
^~~~~~~~~~~~~
arch/um/kernel/process.c:253:5: warning: no previous declaration for 'copy_to_user_proc' [-Wmissing-declarations]
int copy_to_user_proc(void __user *to, void *from, int size)
^~~~~~~~~~~~~~~~~
arch/um/kernel/process.c:263:5: warning: no previous declaration for 'clear_user_proc' [-Wmissing-declarations]
int clear_user_proc(void __user *buf, int size)
^~~~~~~~~~~~~~~
arch/um/kernel/process.c:316:12: warning: no previous declaration for 'make_proc_sysemu' [-Wmissing-declarations]
int __init make_proc_sysemu(void)
^~~~~~~~~~~~~~~~
arch/um/kernel/process.c:356:15: warning: no previous declaration for 'arch_align_stack' [-Wmissing-declarations]
unsigned long arch_align_stack(unsigned long sp)
^~~~~~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from include/linux/oom.h:11,
from arch/um/kernel/reboot.c:11:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/um/kernel/reboot.c: At top level:
arch/um/kernel/reboot.c:45:6: warning: no previous declaration for 'machine_restart' [-Wmissing-declarations]
void machine_restart(char * __unused)
^~~~~~~~~~~~~~~
arch/um/kernel/reboot.c:51:6: warning: no previous declaration for 'machine_power_off' [-Wmissing-declarations]
void machine_power_off(void)
^~~~~~~~~~~~~~~~~
arch/um/kernel/reboot.c:57:6: warning: no previous declaration for 'machine_halt' [-Wmissing-declarations]
void machine_halt(void)
^~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from arch/um/kernel/tlb.c:6:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/um/kernel/tlb.c: At top level:
arch/um/kernel/tlb.c:579:6: warning: no previous declaration for 'flush_tlb_mm_range' [-Wmissing-declarations]
void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
^~~~~~~~~~~~~~~~~~
arch/um/kernel/tlb.c:594:6: warning: no previous declaration for 'force_flush_all' [-Wmissing-declarations]
void force_flush_all(void)
^~~~~~~~~~~~~~~
--
In file included from include/linux/mm.h:29:0,
from arch/um/kernel/um_arch.c:9:
include/linux/pgtable.h: In function 'set_ptes':
>> include/linux/pgtable.h:209:34: error: invalid operands to binary + (have 'pte_t {aka struct <anonymous>}' and 'long unsigned int')
#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
^
include/linux/pgtable.h:238:9: note: in expansion of macro 'pte_next_pfn'
pte = pte_next_pfn(pte);
^~~~~~~~~~~~
arch/um/kernel/um_arch.c: At top level:
arch/um/kernel/um_arch.c:408:19: warning: no previous declaration for 'read_initrd' [-Wmissing-declarations]
int __init __weak read_initrd(void)
^~~~~~~~~~~
arch/um/kernel/um_arch.c:461:7: warning: no previous declaration for 'text_poke' [-Wmissing-declarations]
void *text_poke(void *addr, const void *opcode, size_t len)
^~~~~~~~~
arch/um/kernel/um_arch.c:473:6: warning: no previous declaration for 'text_poke_sync' [-Wmissing-declarations]
void text_poke_sync(void)
^~~~~~~~~~~~~~
..
vim +209 include/linux/pgtable.h
207
208 #ifndef pte_next_pfn
> 209 #define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT))
210 #endif
211
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index d6ad98ca1288..e02b179ec659 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -955,6 +955,14 @@ static inline int pte_same(pte_t a, pte_t b) return a.pte == b.pte; } +static inline pte_t pte_next_pfn(pte_t pte) +{ + if (__pte_needs_invert(pte_val(pte))) + return __pte(pte_val(pte) - (1UL << PFN_PTE_SHIFT)); + return __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); +} +#define pte_next_pfn pte_next_pfn + static inline int pte_present(pte_t a) { return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE); diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 1fba072b3dac..5bdf78aa7852 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -205,6 +205,10 @@ static inline int pmd_young(pmd_t pmd) #define arch_flush_lazy_mmu_mode() do {} while (0) #endif +#ifndef pte_next_pfn +#define pte_next_pfn(pte) ((pte) + (1UL << PFN_PTE_SHIFT)) +#endif + #ifndef set_ptes /** * set_ptes - Map consecutive pages to a contiguous range of addresses. @@ -231,7 +235,7 @@ static inline void set_ptes(struct mm_struct *mm, unsigned long addr, if (--nr == 0) break; ptep++; - pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); + pte = pte_next_pfn(pte); } arch_leave_lazy_mmu_mode(); }
In order to fix the L1TF vulnerability, x86 can invert the PTE bits for PROT_NONE VMAs, which means we cannot move from one PTE to the next by adding 1 to the PFN field of the PTE. Abstract advancing the PTE to the next PFN through a pte_next_pfn() function/macro. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Fixes: bcc6cc832573 ("mm: add default definition of set_ptes()") Reported-by: syzbot+55cc72f8cc3a549119df@syzkaller.appspotmail.com --- arch/x86/include/asm/pgtable.h | 8 ++++++++ include/linux/pgtable.h | 6 +++++- 2 files changed, 13 insertions(+), 1 deletion(-)