Pull MM updates from Andrew Morton:
- In the series "mm: Avoid possible overflows in dirty throttling" Jan
Kara addresses a couple of issues in the writeback throttling code.
These fixes are also targetted at -stable kernels.
- Ryusuke Konishi's series "nilfs2: fix potential issues related to
reserved inodes" does that. This should actually be in the
mm-nonmm-stable tree, along with the many other nilfs2 patches. My
bad.
- More folio conversions from Kefeng Wang in the series "mm: convert to
folio_alloc_mpol()"
- Kemeng Shi has sent some cleanups to the writeback code in the series
"Add helper functions to remove repeated code and improve readability
of cgroup writeback"
- Kairui Song has made the swap code a little smaller and a little
faster in the series "mm/swap: clean up and optimize swap cache
index".
- In the series "mm/memory: cleanly support zeropage in
vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David
Hildenbrand has reworked the rather sketchy handling of the use of
the zeropage in MAP_SHARED mappings. I don't see any runtime effects
here - more a cleanup/understandability/maintainablity thing.
- Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling
of higher addresses, for aarch64. The (poorly named) series is
"Restructure va_high_addr_switch".
- The core TLB handling code gets some cleanups and possible slight
optimizations in Bang Li's series "Add update_mmu_tlb_range() to
simplify code".
- Jane Chu has improved the handling of our
fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in
the series "Enhance soft hwpoison handling and injection".
- Jeff Johnson has sent a billion patches everywhere to add
MODULE_DESCRIPTION() to everything. Some landed in this pull.
- In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang
has simplified migration's use of hardware-offload memory copying.
- Yosry Ahmed performs more folio API conversions in his series "mm:
zswap: trivial folio conversions".
- In the series "large folios swap-in: handle refault cases first",
Chuanhua Han inches us forward in the handling of large pages in the
swap code. This is a cleanup and optimization, working toward the end
objective of full support of large folio swapin/out.
- In the series "mm,swap: cleanup VMA based swap readahead window
calculation", Huang Ying has contributed some cleanups and a possible
fixlet to his VMA based swap readahead code.
- In the series "add mTHP support for anonymous shmem" Baolin Wang has
taught anonymous shmem mappings to use multisize THP. By default this
is a no-op - users must opt in vis sysfs controls. Dramatic
improvements in pagefault latency are realized.
- David Hildenbrand has some cleanups to our remaining use of
page_mapcount() in the series "fs/proc: move page_mapcount() to
fs/proc/internal.h".
- David also has some highmem accounting cleanups in the series
"mm/highmem: don't track highmem pages manually".
- Build-time fixes and cleanups from John Hubbard in the series
"cleanups, fixes, and progress towards avoiding "make headers"".
- Cleanups and consolidation of the core pagemap handling from Barry
Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers
and utilize them".
- Lance Yang's series "Reclaim lazyfree THP without splitting" has
reduced the latency of the reclaim of pmd-mapped THPs under fairly
common circumstances. A 10x speedup is seen in a microbenchmark.
It does this by punting to aother CPU but I guess that's a win unless
all CPUs are pegged.
- hugetlb_cgroup cleanups from Xiu Jianfeng in the series
"mm/hugetlb_cgroup: rework on cftypes".
- Miaohe Lin's series "Some cleanups for memory-failure" does just that
thing.
- Someone other than SeongJae has developed a DAMON feature in Honggyu
Kim's series "DAMON based tiered memory management for CXL memory".
This adds DAMON features which may be used to help determine the
efficiency of our placement of CXL/PCIe attached DRAM.
- DAMON user API centralization and simplificatio work in SeongJae
Park's series "mm/damon: introduce DAMON parameters online commit
function".
- In the series "mm: page_type, zsmalloc and page_mapcount_reset()"
David Hildenbrand does some maintenance work on zsmalloc - partially
modernizing its use of pageframe fields.
- Kefeng Wang provides more folio conversions in the series "mm: remove
page_maybe_dma_pinned() and page_mkclean()".
- More cleanup from David Hildenbrand, this time in the series
"mm/memory_hotplug: use PageOffline() instead of PageReserved() for
!ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline()
pages" and permits the removal of some virtio-mem hacks.
- Barry Song's series "mm: clarify folio_add_new_anon_rmap() and
__folio_add_anon_rmap()" is a cleanup to the anon folio handling in
preparation for mTHP (multisize THP) swapin.
- Kefeng Wang's series "mm: improve clear and copy user folio"
implements more folio conversions, this time in the area of large
folio userspace copying.
- The series "Docs/mm/damon/maintaier-profile: document a mailing tool
and community meetup series" tells people how to get better involved
with other DAMON developers. From SeongJae Park.
- A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does
that.
- David Hildenbrand sends along more cleanups, this time against the
migration code. The series is "mm/migrate: move NUMA hinting fault
folio isolation + checks under PTL".
- Jan Kara has found quite a lot of strangenesses and minor errors in
the readahead code. He addresses this in the series "mm: Fix various
readahead quirks".
- SeongJae Park's series "selftests/damon: test DAMOS tried regions and
{min,max}_nr_regions" adds features and addresses errors in DAMON's
self testing code.
- Gavin Shan has found a userspace-triggerable WARN in the pagecache
code. The series "mm/filemap: Limit page cache size to that supported
by xarray" addresses this. The series is marked cc:stable.
- Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations
and cleanup" cleans up and slightly optimizes KSM.
- Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of
code motion. The series (which also makes the memcg-v1 code
Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put
under config option" and "mm: memcg: put cgroup v1-specific memcg
data under CONFIG_MEMCG_V1"
- Dan Schatzberg's series "Add swappiness argument to memory.reclaim"
adds an additional feature to this cgroup-v2 control file.
- The series "Userspace controls soft-offline pages" from Jiaqi Yan
permits userspace to stop the kernel's automatic treatment of
excessive correctable memory errors. In order to permit userspace to
monitor and handle this situation.
- Kefeng Wang's series "mm: migrate: support poison recover from
migrate folio" teaches the kernel to appropriately handle migration
from poisoned source folios rather than simply panicing.
- SeongJae Park's series "Docs/damon: minor fixups and improvements"
does those things.
- In the series "mm/zsmalloc: change back to per-size_class lock"
Chengming Zhou improves zsmalloc's scalability and memory
utilization.
- Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for
pinning memfd folios" makes the GUP code use FOLL_PIN rather than
bare refcount increments. So these paes can first be moved aside if
they reside in the movable zone or a CMA block.
- Andrii Nakryiko has added a binary ioctl()-based API to
/proc/pid/maps for much faster reading of vma information. The series
is "query VMAs from /proc/<pid>/maps".
- In the series "mm: introduce per-order mTHP split counters" Lance
Yang improves the kernel's presentation of developer information
related to multisize THP splitting.
- Michael Ellerman has developed the series "Reimplement huge pages
without hugepd on powerpc (8xx, e500, book3s/64)". This permits
userspace to use all available huge page sizes.
- In the series "revert unconditional slab and page allocator fault
injection calls" Vlastimil Babka removes a performance-affecting and
not very useful feature from slab fault injection.
* tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits)
mm/mglru: fix ineffective protection calculation
mm/zswap: fix a white space issue
mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio
mm/hugetlb: fix possible recursive locking detected warning
mm/gup: clear the LRU flag of a page before adding to LRU batch
mm/numa_balancing: teach mpol_to_str about the balancing mode
mm: memcg1: convert charge move flags to unsigned long long
alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting
lib: reuse page_ext_data() to obtain codetag_ref
lib: add missing newline character in the warning message
mm/mglru: fix overshooting shrinker memory
mm/mglru: fix div-by-zero in vmpressure_calc_level()
mm/kmemleak: replace strncpy() with strscpy()
mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
mm: ignore data-race in __swap_writepage
hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr
mm: shmem: rename mTHP shmem counters
mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async()
mm/migrate: putback split folios when numa hint migration fails
...
Pull objtool updates from Ingo Molnar: - Fix bug that caused objtool to confuse certain memory ops added by KASAN instrumentation as stack accesses - Various faddr2line optimizations - Improve error messages * tag 'objtool-core-2024-07-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: objtool/x86: objtool can confuse memory and stack access objtool: Use "action" in error message to be consistent with help scripts/faddr2line: Check only two symbols when calculating symbol size scripts/faddr2line: Remove call to addr2line from find_dir_prefix() scripts/faddr2line: Invoke addr2line as a single long-running process scripts/faddr2line: Pass --addresses argument to addr2line scripts/faddr2line: Check vmlinux only once scripts/faddr2line: Combine three readelf calls into one scripts/faddr2line: Reduce number of readelf calls to three
Pull x86 cpu mitigation updates from Borislav Petkov: - Add a spectre_bhi=vmexit mitigation option aimed at cloud environments - Remove duplicated Spectre cmdline option documentation - Add separate macro definitions for syscall handlers which do not return in order to address objtool warnings * tag 'x86_bugs_for_v6.11_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/bugs: Add 'spectre_bhi=vmexit' cmdline option x86/bugs: Remove duplicate Spectre cmdline option descriptions x86/syscall: Mark exit[_group] syscall handlers __noreturn
Like for KASAN, it's useful to temporarily disable KMSAN checks around, e.g., redzone accesses. Introduce kmsan_disable_current() and kmsan_enable_current(), which are similar to their KASAN counterparts. Make them reentrant in order to handle memory allocations in interrupt context. Repurpose the allow_reporting field for this. Link: https://lkml.kernel.org/r/20240621113706.315500-12-iii@linux.ibm.com Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Reviewed-by: Alexander Potapenko <glider@google.com> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: <kasan-dev@googlegroups.com> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Pekka Enberg <penberg@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Steven Rostedt (Google) <rostedt@goodmis.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The encoding of an x86 instruction can include a ModR/M and a SIB (Scale-Index-Base) byte to describe the addressing mode of the instruction. objtool processes all addressing mode with a SIB base of 5 as having %rbp as the base register. However, a SIB base of 5 means that the effective address has either no base (if ModR/M mod is zero) or %rbp as the base (if ModR/M mod is 1 or 2). This can cause objtool to confuse an absolute address access with a stack operation. For example, objtool will see the following instruction: 4c 8b 24 25 e0 ff ff mov 0xffffffffffffffe0,%r12 as a stack operation (i.e. similar to: mov -0x20(%rbp), %r12). [Note that this kind of weird absolute address access is added by the compiler when using KASAN.] If this perceived stack operation happens to reference the location where %r12 was pushed on the stack then the objtool validation will think that %r12 is being restored and this can cause a stack state mismatch. This kind behavior was seen on xfs code, after a minor change (convert kmem_alloc() to kmalloc()): >> fs/xfs/xfs.o: warning: objtool: xfs_da_grow_inode_int+0x6c1: stack state mismatch: reg1[12]=-2-48 reg2[12]=-1+0 Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202402220435.MGN0EV6l-lkp@intel.com/ Signed-off-by: Alexandre Chartre <alexandre.chartre@oracle.com> Link: https://lore.kernel.org/r/20240620144747.2524805-1-alexandre.chartre@oracle.com Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
The help message mentions the main options as "actions", which is different from the optional "options". But the check error messages outputs "option" or "command" for referring to actions. Make the error messages consistent with help. Signed-off-by: Siddh Raman Pant <siddh.raman.pant@oracle.com> Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
objtool complains: arch/x86/kvm/kvm.o: warning: objtool: .altinstr_replacement+0xc5: call without frame pointer save/setup vmlinux.o: warning: objtool: .altinstr_replacement+0x2eb: call without frame pointer save/setup Make sure %rSP is an output operand to the respective asm() statements. The test_cc() hunk and ALT_OUTPUT_SP() courtesy of peterz. Also from him add some helpful debugging info to the documentation. Now on to the explanations: tl;dr: The alternatives macros are pretty fragile. If I do ALT_OUTPUT_SP(output) in order to be able to package in a %rsp reference for objtool so that a stack frame gets properly generated, the inline asm input operand with positional argument 0 in clear_page(): "0" (page) gets "renumbered" due to the added : "+r" (current_stack_pointer), "=D" (page) and then gcc says: ./arch/x86/include/asm/page_64.h:53:9: error: inconsistent operand constraints in an ‘asm’ The fix is to use an explicit "D" constraint which points to a singleton register class (gcc terminology) which ends up doing what is expected here: the page pointer - input and output - should be in the same %rdi register. Other register classes have more than one register in them - example: "r" and "=r" or "A": ‘A’ The ‘a’ and ‘d’ registers. This class is used for instructions that return double word results in the ‘ax:dx’ register pair. Single word values will be allocated either in ‘ax’ or ‘dx’. so using "D" and "=D" just works in this particular case. And yes, one would say, sure, why don't you do "+D" but then: : "+r" (current_stack_pointer), "+D" (page) : [old] "i" (clear_page_orig), [new1] "i" (clear_page_rep), [new2] "i" (clear_page_erms), : "cc", "memory", "rax", "rcx") now find the Waldo^Wcomma which throws a wrench into all this. Because that silly macro has an "input..." consume-all last macro arg and in it, one is supposed to supply input *and* clobbers, leading to silly syntax snafus. Yap, they need to be cleaned up, one fine day... Closes: https://lore.kernel.org/oe-kbuild-all/202406141648.jO9qNGLa-lkp@intel.com/ Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Acked-by: Sean Christopherson <seanjc@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20240625112056.GDZnqoGDXgYuWBDUwu@fat_crate.local
The direct-call syscall dispatch function doesn't know that the exit()
and exit_group() syscall handlers don't return, so the call sites aren't
optimized accordingly.
Fix that by marking the exit syscall declarations __noreturn.
Fixes the following warnings:
vmlinux.o: warning: objtool: x64_sys_call+0x2804: __x64_sys_exit() is missing a __noreturn annotation
vmlinux.o: warning: objtool: ia32_sys_call+0x29b6: __ia32_sys_exit_group() is missing a __noreturn annotation
Fixes: 1e3ad78334a6 ("x86/syscall: Don't force use of indirect calls for system calls")
Closes: https://lkml.kernel.org/lkml/6dba9b32-db2c-4e6d-9500-7a08852f17a3@paulmck-laptop
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/5d8882bc077d8eadcc7fd1740b56dfb781f12288.1719381528.git.jpoimboe@kernel.org
Instead of making increasingly complicated ALTERNATIVE_n()
implementations, use a nested alternative expression.
The only difference between:
ALTERNATIVE_2(oldinst, newinst1, flag1, newinst2, flag2)
and
ALTERNATIVE(ALTERNATIVE(oldinst, newinst1, flag1),
newinst2, flag2)
is that the outer alternative can add additional padding when the inner
alternative is the shorter one, which then results in
alt_instr::instrlen being inconsistent.
However, this is easily remedied since the alt_instr entries will be
consecutive and it is trivial to compute the max(alt_instr::instrlen) at
runtime while patching.
Specifically, after this the ALTERNATIVE_2 macro, after CPP expansion
(and manual layout), looks like this:
.macro ALTERNATIVE_2 oldinstr, newinstr1, ft_flags1, newinstr2, ft_flags2
740:
740: \oldinstr ;
741: .skip -(((744f-743f)-(741b-740b)) > 0) * ((744f-743f)-(741b-740b)),0x90 ;
742: .pushsection .altinstructions,"a" ;
altinstr_entry 740b,743f,\ft_flags1,742b-740b,744f-743f ;
.popsection ;
.pushsection .altinstr_replacement,"ax" ;
743: \newinstr1 ;
744: .popsection ; ;
741: .skip -(((744f-743f)-(741b-740b)) > 0) * ((744f-743f)-(741b-740b)),0x90 ;
742: .pushsection .altinstructions,"a" ;
altinstr_entry 740b,743f,\ft_flags2,742b-740b,744f-743f ;
.popsection ;
.pushsection .altinstr_replacement,"ax" ;
743: \newinstr2 ;
744: .popsection ;
.endm
The only label that is ambiguous is 740, however they all reference the
same spot, so that doesn't matter.
NOTE: obviously only @oldinstr may be an alternative; making @newinstr
an alternative would mean patching .altinstr_replacement which very
likely isn't what is intended, also the labels will be confused in that
case.
[ bp: Debug an issue where it would match the wrong two insns and
and consider them nested due to the same signed offsets in the
.alternative section and use instr_va() to compare the full virtual
addresses instead.
- Use new labels to denote that the new, nested
alternatives are being used when staring at preprocessed output.
- Use the %c constraint everywhere instead of %P and document the
difference for future reference. ]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230628104952.GA2439977@hirez.programming.kicks-ass.net
When compiling the v6.9-rc1 kernel with the x32 compiler, the following
errors are reported. The reason is that we take an "unsigned long"
variable and print it using "PRIx64" format string.
In file included from check.c:16:
check.c: In function ‘add_dead_ends’:
/usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:46:17: error: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 5 has type ‘long unsigned int’ [-Werror=format=]
46 | "%s: warning: objtool: " format "\n", \
| ^~~~~~~~~~~~~~~~~~~~~~~~
check.c:613:33: note: in expansion of macro ‘WARN’
613 | WARN("can't find unreachable insn at %s+0x%" PRIx64,
| ^~~~
...
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: linux-kernel@vger.kernel.org