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2022-01-07Merge tag 'drm-fixes-2022-01-07' of git://anongit.freedesktop.org/drm/drmLinus Torvalds
Pull drm fixes from Dave Airlie: "There is only the amdgpu runtime pm regression fix in here: amdgpu: - suspend/resume fix - fix runtime PM regression" * tag 'drm-fixes-2022-01-07' of git://anongit.freedesktop.org/drm/drm: drm/amdgpu: disable runpm if we are the primary adapter fbdev: fbmem: add a helper to determine if an aperture is used by a fw fb drm/amd/pm: keep the BACO feature enabled for suspend
2022-01-07KVM: x86: Check for rmaps allocationNikunj A Dadhania
With TDP MMU being the default now, access to mmu_rmaps_stat debugfs file causes following oops: BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 7 PID: 3185 Comm: cat Not tainted 5.16.0-rc4+ #204 RIP: 0010:pte_list_count+0x6/0x40 Call Trace: <TASK> ? kvm_mmu_rmaps_stat_show+0x15e/0x320 seq_read_iter+0x126/0x4b0 ? aa_file_perm+0x124/0x490 seq_read+0xf5/0x140 full_proxy_read+0x5c/0x80 vfs_read+0x9f/0x1a0 ksys_read+0x67/0xe0 __x64_sys_read+0x19/0x20 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fca6fc13912 Return early when rmaps are not present. Reported-by: Vasant Hegde <vasant.hegde@amd.com> Tested-by: Vasant Hegde <vasant.hegde@amd.com> Signed-off-by: Nikunj A Dadhania <nikunj@amd.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Sean Christopherson <seanjc@google.com> Message-Id: <20220105040337.4234-1-nikunj@amd.com> Cc: stable@vger.kernel.org Fixes: 3bcd0662d66f ("KVM: X86: Introduce mmu_rmaps_stat per-vm debugfs file") Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-07KVM: SEV: Mark nested locking of kvm->lockWanpeng Li
Both source and dest vms' kvm->locks are held in sev_lock_two_vms. Mark one with a different subtype to avoid false positives from lockdep. Fixes: c9d61dcb0bc26 (KVM: SEV: accept signals in sev_lock_two_vms) Reported-by: Yiru Xu <xyru1999@gmail.com> Tested-by: Jinrong Liang <cloudliang@tencent.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1641364863-26331-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-01-07x86/sgx: Fix NULL pointer dereference on non-SGX systemsDave Hansen
== Problem == Nathan Chancellor reported an oops when aceessing the 'sgx_total_bytes' sysfs file: https://lore.kernel.org/all/YbzhBrimHGGpddDM@archlinux-ax161/ The sysfs output code accesses the sgx_numa_nodes[] array unconditionally. However, this array is allocated during SGX initialization, which only occurs on systems where SGX is supported. If the sysfs file is accessed on systems without SGX support, sgx_numa_nodes[] is NULL and an oops occurs. == Solution == To fix this, hide the entire nodeX/x86/ attribute group on systems without SGX support using the ->is_visible attribute group callback. Unfortunately, SGX is initialized via a device_initcall() which occurs _after_ the ->is_visible() callback. Instead of moving SGX initialization earlier, call sysfs_update_group() during SGX initialization to update the group visiblility. This update requires moving the SGX sysfs code earlier in sgx/main.c. There are no code changes other than the addition of arch_update_sysfs_visibility() and a minor whitespace fixup to arch_node_attr_is_visible() which checkpatch caught. CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-sgx@vger.kernel.org Cc: x86@kernel.org Fixes: 50468e431335 ("x86/sgx: Add an attribute for the amount of SGX memory in a NUMA node") Reported-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Link: https://lkml.kernel.org/r/20220104171527.5E8416A8@davehans-spike.ostc.intel.com
2022-01-07s390/pci: simplify __pciwb_mio() inline asmNiklas Schnelle
The PCI Write Barrier instruction ignores the registers encoded in it. There is thus no need to explicitly set the register to zero or to associate it with a variable at all. In the resulting binary this removes an unnecessary lghi and it makes the code simpler. Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-01-07Merge branch 'for-5.17/struct-slab' into for-linusVlastimil Babka
Series "Separate struct slab from struct page" v4 This is originally an offshoot of the folio work by Matthew. One of the more complex parts of the struct page definition are the parts used by the slab allocators. It would be good for the MM in general if struct slab were its own data type, and it also helps to prevent tail pages from slipping in anywhere. As Matthew requested in his proof of concept series, I have taken over the development of this series, so it's a mix of patches from him (often modified by me) and my own. One big difference is the use of coccinelle to perform the relatively trivial parts of the conversions automatically and at once, instead of a larger number of smaller incremental reviewable steps. Thanks to Julia Lawall and Luis Chamberlain for all their help! Another notable difference is (based also on review feedback) I don't represent with a struct slab the large kmalloc allocations which are not really a slab, but use page allocator directly. When going from an object address to a struct slab, the code tests first folio slab flag, and only if it's set it converts to struct slab. This makes the struct slab type stronger. Finally, although Matthew's version didn't use any of the folio work, the initial support has been merged meanwhile so my version builds on top of it where appropriate. This eliminates some of the redundant compound_head() being performed e.g. when testing the slab flag. To sum up, after this series, struct page fields used by slab allocators are moved from struct page to a new struct slab, that uses the same physical storage. The availability of the fields is further distinguished by the selected slab allocator implementation. The advantages include: - Similar to folios, if the slab is of order > 0, struct slab always is guaranteed to be the head page. Additionally it's guaranteed to be an actual slab page, not a large kmalloc. This removes uncertainty and potential for bugs. - It's not possible to accidentally use fields of the slab implementation that's not configured. - Other subsystems cannot use slab's fields in struct page anymore (some existing non-slab usages had to be adjusted in this series), so slab implementations have more freedom in rearranging them in the struct slab. Link: https://lore.kernel.org/all/20220104001046.12263-1-vbabka@suse.cz/
2022-01-06Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdmaLinus Torvalds
Pull rdma fixes from Jason Gunthorpe: "Last pull for 5.16, the reversion has been known for a while now but didn't get a proper fix in time. Looks like we will have several info-leak bugs to take care of going foward. - Revert the patch fixing the DM related crash causing a widespread regression for kernel ULPs. A proper fix just didn't appear this cycle due to the holidays - Missing NULL check on alloc in uverbs - Double free in rxe error paths - Fix a new kernel-infoleak report when forming ah_attr's without GRH's in ucma" * tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: RDMA/core: Don't infoleak GRH fields RDMA/uverbs: Check for null return of kmalloc_array Revert "RDMA/mlx5: Fix releasing unallocated memory in dereg MR flow" RDMA/rxe: Prevent double freeing rxe_map_set()
2022-01-07random: don't reset crng_init_cnt on urandom_read()Jann Horn
At the moment, urandom_read() (used for /dev/urandom) resets crng_init_cnt to zero when it is called at crng_init<2. This is inconsistent: We do it for /dev/urandom reads, but not for the equivalent getrandom(GRND_INSECURE). (And worse, as Jason pointed out, we're only doing this as long as maxwarn>0.) crng_init_cnt is only read in crng_fast_load(); it is relevant at crng_init==0 for determining when to switch to crng_init==1 (and where in the RNG state array to write). As far as I understand: - crng_init==0 means "we have nothing, we might just be returning the same exact numbers on every boot on every machine, we don't even have non-cryptographic randomness; we should shove every bit of entropy we can get into the RNG immediately" - crng_init==1 means "well we have something, it might not be cryptographic, but at least we're not gonna return the same data every time or whatever, it's probably good enough for TCP and ASLR and stuff; we now have time to build up actual cryptographic entropy in the input pool" - crng_init==2 means "this is supposed to be cryptographically secure now, but we'll keep adding more entropy just to be sure". The current code means that if someone is pulling data from /dev/urandom fast enough at crng_init==0, we'll keep resetting crng_init_cnt, and we'll never make forward progress to crng_init==1. It seems to be intended to prevent an attacker from bruteforcing the contents of small individual RNG inputs on the way from crng_init==0 to crng_init==1, but that's misguided; crng_init==1 isn't supposed to provide proper cryptographic security anyway, RNG users who care about getting secure RNG output have to wait until crng_init==2. This code was inconsistent, and it probably made things worse - just get rid of it. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: avoid superfluous call to RDRAND in CRNG extractionJason A. Donenfeld
RDRAND is not fast. RDRAND is actually quite slow. We've known this for a while, which is why functions like get_random_u{32,64} were converted to use batching of our ChaCha-based CRNG instead. Yet CRNG extraction still includes a call to RDRAND, in the hot path of every call to get_random_bytes(), /dev/urandom, and getrandom(2). This call to RDRAND here seems quite superfluous. CRNG is already extracting things based on a 256-bit key, based on good entropy, which is then reseeded periodically, updated, backtrack-mutated, and so forth. The CRNG extraction construction is something that we're already relying on to be secure and solid. If it's not, that's a serious problem, and it's unlikely that mixing in a measly 32 bits from RDRAND is going to alleviate things. And in the case where the CRNG doesn't have enough entropy yet, we're already initializing the ChaCha key row with RDRAND in crng_init_try_arch_early(). Removing the call to RDRAND improves performance on an i7-11850H by 370%. In other words, the vast majority of the work done by extract_crng() prior to this commit was devoted to fetching 32 bits of RDRAND. Reviewed-by: Theodore Ts'o <tytso@mit.edu> Acked-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: early initialization of ChaCha constantsDominik Brodowski
Previously, the ChaCha constants for the primary pool were only initialized in crng_initialize_primary(), called by rand_initialize(). However, some randomness is actually extracted from the primary pool beforehand, e.g. by kmem_cache_create(). Therefore, statically initialize the ChaCha constants for the primary pool. Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: <linux-crypto@vger.kernel.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: use IS_ENABLED(CONFIG_NUMA) instead of ifdefsJason A. Donenfeld
Rather than an awkward combination of ifdefs and __maybe_unused, we can ensure more source gets parsed, regardless of the configuration, by using IS_ENABLED for the CONFIG_NUMA conditional code. This makes things cleaner and easier to follow. I've confirmed that on !CONFIG_NUMA, we don't wind up with excess code by accident; the generated object file is the same. Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: harmonize "crng init done" messagesDominik Brodowski
We print out "crng init done" for !TRUST_CPU, so we should also print out the same for TRUST_CPU. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: mix bootloader randomness into poolJason A. Donenfeld
If we're trusting bootloader randomness, crng_fast_load() is called by add_hwgenerator_randomness(), which sets us to crng_init==1. However, usually it is only called once for an initial 64-byte push, so bootloader entropy will not mix any bytes into the input pool. So it's conceivable that crng_init==1 when crng_initialize_primary() is called later, but then the input pool is empty. When that happens, the crng state key will be overwritten with extracted output from the empty input pool. That's bad. In contrast, if we're not trusting bootloader randomness, we call crng_slow_load() *and* we call mix_pool_bytes(), so that later crng_initialize_primary() isn't drawing on nothing. In order to prevent crng_initialize_primary() from extracting an empty pool, have the trusted bootloader case mirror that of the untrusted bootloader case, mixing the input into the pool. [linux@dominikbrodowski.net: rewrite commit message] Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: do not throw away excess input to crng_fast_loadJason A. Donenfeld
When crng_fast_load() is called by add_hwgenerator_randomness(), we currently will advance to crng_init==1 once we've acquired 64 bytes, and then throw away the rest of the buffer. Usually, that is not a problem: When add_hwgenerator_randomness() gets called via EFI or DT during setup_arch(), there won't be any IRQ randomness. Therefore, the 64 bytes passed by EFI exactly matches what is needed to advance to crng_init==1. Usually, DT seems to pass 64 bytes as well -- with one notable exception being kexec, which hands over 128 bytes of entropy to the kexec'd kernel. In that case, we'll advance to crng_init==1 once 64 of those bytes are consumed by crng_fast_load(), but won't continue onward feeding in bytes to progress to crng_init==2. This commit fixes the issue by feeding any leftover bytes into the next phase in add_hwgenerator_randomness(). [linux@dominikbrodowski.net: rewrite commit message] Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: do not re-init if crng_reseed completes before primary initJason A. Donenfeld
If the bootloader supplies sufficient material and crng_reseed() is called very early on, but not too early that wqs aren't available yet, then we might transition to crng_init==2 before rand_initialize()'s call to crng_initialize_primary() made. Then, when crng_initialize_primary() is called, if we're trusting the CPU's RDRAND instructions, we'll needlessly reinitialize the RNG and emit a message about it. This is mostly harmless, as numa_crng_init() will allocate and then free what it just allocated, and excessive calls to invalidate_batched_entropy() aren't so harmful. But it is funky and the extra message is confusing, so avoid the re-initialization all together by checking for crng_init < 2 in crng_initialize_primary(), just as we already do in crng_reseed(). Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: fix crash on multiple early calls to add_bootloader_randomness()Dominik Brodowski
Currently, if CONFIG_RANDOM_TRUST_BOOTLOADER is enabled, multiple calls to add_bootloader_randomness() are broken and can cause a NULL pointer dereference, as noted by Ivan T. Ivanov. This is not only a hypothetical problem, as qemu on arm64 may provide bootloader entropy via EFI and via devicetree. On the first call to add_hwgenerator_randomness(), crng_fast_load() is executed, and if the seed is long enough, crng_init will be set to 1. On subsequent calls to add_bootloader_randomness() and then to add_hwgenerator_randomness(), crng_fast_load() will be skipped. Instead, wait_event_interruptible() and then credit_entropy_bits() will be called. If the entropy count for that second seed is large enough, that proceeds to crng_reseed(). However, both wait_event_interruptible() and crng_reseed() depends (at least in numa_crng_init()) on workqueues. Therefore, test whether system_wq is already initialized, which is a sufficient indicator that workqueue_init_early() has progressed far enough. If we wind up hitting the !system_wq case, we later want to do what would have been done there when wqs are up, so set a flag, and do that work later from the rand_initialize() call. Reported-by: Ivan T. Ivanov <iivanov@suse.de> Fixes: 18b915ac6b0a ("efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness") Cc: stable@vger.kernel.org Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> [Jason: added crng_need_done state and related logic.] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: do not sign extend bytes for rotation when mixingJason A. Donenfeld
By using `char` instead of `unsigned char`, certain platforms will sign extend the byte when `w = rol32(*bytes++, input_rotate)` is called, meaning that bit 7 is overrepresented when mixing. This isn't a real problem (unless the mixer itself is already broken) since it's still invertible, but it's not quite correct either. Fix this by using an explicit unsigned type. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: use BLAKE2s instead of SHA1 in extractionJason A. Donenfeld
This commit addresses one of the lower hanging fruits of the RNG: its usage of SHA1. BLAKE2s is generally faster, and certainly more secure, than SHA1, which has [1] been [2] really [3] very [4] broken [5]. Additionally, the current construction in the RNG doesn't use the full SHA1 function, as specified, and allows overwriting the IV with RDRAND output in an undocumented way, even in the case when RDRAND isn't set to "trusted", which means potential malicious IV choices. And its short length means that keeping only half of it secret when feeding back into the mixer gives us only 2^80 bits of forward secrecy. In other words, not only is the choice of hash function dated, but the use of it isn't really great either. This commit aims to fix both of these issues while also keeping the general structure and semantics as close to the original as possible. Specifically: a) Rather than overwriting the hash IV with RDRAND, we put it into BLAKE2's documented "salt" and "personal" fields, which were specifically created for this type of usage. b) Since this function feeds the full hash result back into the entropy collector, we only return from it half the length of the hash, just as it was done before. This increases the construction's forward secrecy from 2^80 to a much more comfortable 2^128. c) Rather than using the raw "sha1_transform" function alone, we instead use the full proper BLAKE2s function, with finalization. This also has the advantage of supplying 16 bytes at a time rather than SHA1's 10 bytes, which, in addition to having a faster compression function to begin with, means faster extraction in general. On an Intel i7-11850H, this commit makes initial seeding around 131% faster. BLAKE2s itself has the nice property of internally being based on the ChaCha permutation, which the RNG is already using for expansion, so there shouldn't be any issue with newness, funkiness, or surprising CPU behavior, since it's based on something already in use. [1] https://eprint.iacr.org/2005/010.pdf [2] https://www.iacr.org/archive/crypto2005/36210017/36210017.pdf [3] https://eprint.iacr.org/2015/967.pdf [4] https://shattered.io/static/shattered.pdf [5] https://www.usenix.org/system/files/sec20-leurent.pdf Reviewed-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Jean-Philippe Aumasson <jeanphilippe.aumasson@gmail.com> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07lib/crypto: blake2s: include as built-inJason A. Donenfeld
In preparation for using blake2s in the RNG, we change the way that it is wired-in to the build system. Instead of using ifdefs to select the right symbol, we use weak symbols. And because ARM doesn't need the generic implementation, we make the generic one default only if an arch library doesn't need it already, and then have arch libraries that do need it opt-in. So that the arch libraries can remain tristate rather than bool, we then split the shash part from the glue code. Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: linux-kbuild@vger.kernel.org Cc: linux-crypto@vger.kernel.org Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: fix data race on crng init timeEric Biggers
_extract_crng() does plain loads of crng->init_time and crng_global_init_time, which causes undefined behavior if crng_reseed() and RNDRESEEDCRNG modify these corrently. Use READ_ONCE() and WRITE_ONCE() to make the behavior defined. Don't fix the race on crng->init_time by protecting it with crng->lock, since it's not a problem for duplicate reseedings to occur. I.e., the lockless access with READ_ONCE() is fine. Fixes: d848e5f8e1eb ("random: add new ioctl RNDRESEEDCRNG") Fixes: e192be9d9a30 ("random: replace non-blocking pool with a Chacha20-based CRNG") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: fix data race on crng_node_poolEric Biggers
extract_crng() and crng_backtrack_protect() load crng_node_pool with a plain load, which causes undefined behavior if do_numa_crng_init() modifies it concurrently. Fix this by using READ_ONCE(). Note: as per the previous discussion https://lore.kernel.org/lkml/20211219025139.31085-1-ebiggers@kernel.org/T/#u, READ_ONCE() is believed to be sufficient here, and it was requested that it be used here instead of smp_load_acquire(). Also change do_numa_crng_init() to set crng_node_pool using cmpxchg_release() instead of mb() + cmpxchg(), as the former is sufficient here but is more lightweight. Fixes: 1e7f583af67b ("random: make /dev/urandom scalable for silly userspace programs") Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07irq: remove unused flags argument from __handle_irq_event_percpu()Sebastian Andrzej Siewior
The __IRQF_TIMER bit from the flags argument was used in add_interrupt_randomness() to distinguish the timer interrupt from other interrupts. This is no longer the case. Remove the flags argument from __handle_irq_event_percpu(). Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: remove unused irq_flags argument from add_interrupt_randomness()Sebastian Andrzej Siewior
Since commit ee3e00e9e7101 ("random: use registers from interrupted code for CPU's w/o a cycle counter") the irq_flags argument is no longer used. Remove unused irq_flags. Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dexuan Cui <decui@microsoft.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: K. Y. Srinivasan <kys@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wei Liu <wei.liu@kernel.org> Cc: linux-hyperv@vger.kernel.org Cc: x86@kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Wei Liu <wei.liu@kernel.org> Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07random: document add_hwgenerator_randomness() with other input functionsMark Brown
The section at the top of random.c which documents the input functions available does not document add_hwgenerator_randomness() which might lead a reader to overlook it. Add a brief note about it. Signed-off-by: Mark Brown <broonie@kernel.org> [Jason: reorganize position of function in doc comment and also document add_bootloader_randomness() while we're at it.] Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-07MAINTAINERS: add git tree for random.cJason A. Donenfeld
This is handy not just for humans, but also so that the 0-day bot can automatically test posted mailing list patches against the right tree. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-01-06Merge tag 'trace-v5.16-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Three minor tracing fixes: - Fix missing prototypes in sample module for direct functions - Fix check of valid buffer in get_trace_buf() - Fix annotations of percpu pointers" * tag 'trace-v5.16-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Tag trace_percpu_buffer as a percpu pointer tracing: Fix check for trace_percpu_buffer validity in get_trace_buf() ftrace/samples: Add missing prototypes direct functions
2022-01-06selftests: cgroup: Test open-time cgroup namespace usage for migration checksTejun Heo
When a task is writing to an fd opened by a different task, the perm check should use the cgroup namespace of the latter task. Add a test for it. Tested-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06selftests: cgroup: Test open-time credential usage for migration checksTejun Heo
When a task is writing to an fd opened by a different task, the perm check should use the credentials of the latter task. Add a test for it. Tested-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06selftests: cgroup: Make cg_create() use 0755 for permission instead of 0644Tejun Heo
0644 is an odd perm to create a cgroup which is a directory. Use the regular 0755 instead. This is necessary for euid switching test case. Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06cgroup: Use open-time cgroup namespace for process migration perm checksTejun Heo
cgroup process migration permission checks are performed at write time as whether a given operation is allowed or not is dependent on the content of the write - the PID. This currently uses current's cgroup namespace which is a potential security weakness as it may allow scenarios where a less privileged process tricks a more privileged one into writing into a fd that it created. This patch makes cgroup remember the cgroup namespace at the time of open and uses it for migration permission checks instad of current's. Note that this only applies to cgroup2 as cgroup1 doesn't have namespace support. This also fixes a use-after-free bug on cgroupns reported in https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com Note that backporting this fix also requires the preceding patch. Reported-by: "Eric W. Biederman" <ebiederm@xmission.com> Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Reported-by: syzbot+50f5cf33a284ce738b62@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/00000000000048c15c05d0083397@google.com Fixes: 5136f6365ce3 ("cgroup: implement "nsdelegate" mount option") Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-06cgroup: Allocate cgroup_file_ctx for kernfs_open_file->privTejun Heo
of->priv is currently used by each interface file implementation to store private information. This patch collects the current two private data usages into struct cgroup_file_ctx which is allocated and freed by the common path. This allows generic private data which applies to multiple files, which will be used to in the following patch. Note that cgroup_procs iterator is now embedded as procs.iter in the new cgroup_file_ctx so that it doesn't need to be allocated and freed separately. v2: union dropped from cgroup_file_ctx and the procs iterator is embedded in cgroup_file_ctx as suggested by Linus. v3: Michal pointed out that cgroup1's procs pidlist uses of->priv too. Converted. Didn't change to embedded allocation as cgroup1 pidlists get stored for caching. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Michal Koutný <mkoutny@suse.com>
2022-01-06cgroup: Use open-time credentials for process migraton perm checksTejun Heo
cgroup process migration permission checks are performed at write time as whether a given operation is allowed or not is dependent on the content of the write - the PID. This currently uses current's credentials which is a potential security weakness as it may allow scenarios where a less privileged process tricks a more privileged one into writing into a fd that it created. This patch makes both cgroup2 and cgroup1 process migration interfaces to use the credentials saved at the time of open (file->f_cred) instead of current's. Reported-by: "Eric W. Biederman" <ebiederm@xmission.com> Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Fixes: 187fe84067bd ("cgroup: require write perm on common ancestor when moving processes on the default hierarchy") Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2022-01-07Merge tag 'amd-drm-fixes-5.16-2021-12-31' of ↵Dave Airlie
ssh://gitlab.freedesktop.org/agd5f/linux into drm-fixes amd-drm-fixes-5.16-2021-12-31: amdgpu: - Suspend/resume fix - Restore runtime pm behavior with efifb Signed-off-by: Dave Airlie <airlied@redhat.com> From: Alex Deucher <alexander.deucher@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20211231143825.11479-1-alexander.deucher@amd.com
2022-01-06i2c: mpc: Avoid out of bounds memory accessChris Packham
When performing an I2C transfer where the last message was a write KASAN would complain: BUG: KASAN: slab-out-of-bounds in mpc_i2c_do_action+0x154/0x630 Read of size 2 at addr c814e310 by task swapper/2/0 CPU: 2 PID: 0 Comm: swapper/2 Tainted: G B 5.16.0-rc8 #1 Call Trace: [e5ee9d50] [c08418e8] dump_stack_lvl+0x4c/0x6c (unreliable) [e5ee9d70] [c02f8a14] print_address_description.constprop.13+0x64/0x3b0 [e5ee9da0] [c02f9030] kasan_report+0x1f0/0x204 [e5ee9de0] [c0c76ee4] mpc_i2c_do_action+0x154/0x630 [e5ee9e30] [c0c782c4] mpc_i2c_isr+0x164/0x240 [e5ee9e60] [c00f3a04] __handle_irq_event_percpu+0xf4/0x3b0 [e5ee9ec0] [c00f3d40] handle_irq_event_percpu+0x80/0x110 [e5ee9f40] [c00f3e48] handle_irq_event+0x78/0xd0 [e5ee9f60] [c00fcfec] handle_fasteoi_irq+0x19c/0x370 [e5ee9fa0] [c00f1d84] generic_handle_irq+0x54/0x80 [e5ee9fc0] [c0006b54] __do_irq+0x64/0x200 [e5ee9ff0] [c0007958] __do_IRQ+0xe8/0x1c0 [c812dd50] [e3eaab20] 0xe3eaab20 [c812dd90] [c0007a4c] do_IRQ+0x1c/0x30 [c812dda0] [c0000c04] ExternalInput+0x144/0x160 --- interrupt: 500 at arch_cpu_idle+0x34/0x60 NIP: c000b684 LR: c000b684 CTR: c0019688 REGS: c812ddb0 TRAP: 0500 Tainted: G B (5.16.0-rc8) MSR: 00029002 <CE,EE,ME> CR: 22000488 XER: 20000000 GPR00: c10ef7fc c812de90 c80ff200 c2394718 00000001 00000001 c10e3f90 00000003 GPR08: 00000000 c0019688 c2394718 fc7d625b 22000484 00000000 21e17000 c208228c GPR16: e3e99284 00000000 ffffffff c2390000 c001bac0 c2082288 c812df60 c001ba60 GPR24: c23949c0 00000018 00080000 00000004 c80ff200 00000002 c2348ee4 c2394718 NIP [c000b684] arch_cpu_idle+0x34/0x60 LR [c000b684] arch_cpu_idle+0x34/0x60 --- interrupt: 500 [c812de90] [c10e3f90] rcu_eqs_enter.isra.60+0xc0/0x110 (unreliable) [c812deb0] [c10ef7fc] default_idle_call+0xbc/0x230 [c812dee0] [c00af0e8] do_idle+0x1c8/0x200 [c812df10] [c00af3c0] cpu_startup_entry+0x20/0x30 [c812df20] [c001e010] start_secondary+0x5d0/0xba0 [c812dff0] [c00028a0] __secondary_start+0x90/0xdc This happened because we would overrun the i2c->msgs array on the final interrupt for the I2C STOP. This didn't happen if the last message was a read because there is no interrupt in that case. Ensure that we only access the current message if we are not processing a I2C STOP condition. Fixes: 1538d82f4647 ("i2c: mpc: Interrupt driven transfer") Reported-by: Maxime Bizon <mbizon@freebox.fr> Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-01-06mm/slob: Remove unnecessary page_mapcount_reset() function callHyeonggon Yoo
After commit 401fb12c68c2 ("mm/sl*b: Differentiate struct slab fields by sl*b implementations"), we can reorder fields of struct slab depending on slab allocator. For now, page_mapcount_reset() is called because page->_mapcount and slab->units have same offset. But this is not necessary for struct slab. Use unused field for units instead. Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Link: https://lore.kernel.org/r/20211212065241.GA886691@odroid
2022-01-06bootmem: Use page->index instead of page->freelistMatthew Wilcox (Oracle)
page->freelist is for the use of slab. Using page->index is the same set of bits as page->freelist, and by using an integer instead of a pointer, we can avoid casts. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: <x86@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com>
2022-01-06zsmalloc: Stop using slab fields in struct pageMatthew Wilcox (Oracle)
The ->freelist and ->units members of struct page are for the use of slab only. I'm not particularly familiar with zsmalloc, so generate the same code by using page->index to store 'page' (page->index and page->freelist are at the same offset in struct page). This should be cleaned up properly at some point by somebody who is familiar with zsmalloc. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Minchan Kim <minchan@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
2022-01-06mm/slub: Define struct slab fields for CONFIG_SLUB_CPU_PARTIAL only when enabledVlastimil Babka
The fields 'next' and 'slabs' are only used when CONFIG_SLUB_CPU_PARTIAL is enabled. We can put their definition to #ifdef to prevent accidental use when disabled. Currenlty show_slab_objects() and slabs_cpu_partial_show() contain code accessing the slabs field that's effectively dead with CONFIG_SLUB_CPU_PARTIAL=n through the wrappers slub_percpu_partial() and slub_percpu_partial_read_once(), but to prevent a compile error, we need to hide all this code behind #ifdef. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Roman Gushchin <guro@fb.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06mm/slub: Simplify struct slab slabs field definitionVlastimil Babka
Before commit b47291ef02b0 ("mm, slub: change percpu partial accounting from objects to pages") we had to fit two integer fields into a native word size, so we used short int on 32-bit and int on 64-bit via #ifdef. After that commit there is only one integer field, so we can simply define it as int everywhere. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06mm/sl*b: Differentiate struct slab fields by sl*b implementationsVlastimil Babka
With a struct slab definition separate from struct page, we can go further and define only fields that the chosen sl*b implementation uses. This means everything between __page_flags and __page_refcount placeholders now depends on the chosen CONFIG_SL*B. Some fields exist in all implementations (slab_list) but can be part of a union in some, so it's simpler to repeat them than complicate the definition with ifdefs even more. The patch doesn't change physical offsets of the fields, although it could be done later - for example it's now clear that tighter packing in SLOB could be possible. This should also prevent accidental use of fields that don't exist in given implementation. Before this patch virt_to_cache() and cache_from_obj() were visible for SLOB (albeit not used), although they rely on the slab_cache field that isn't set by SLOB. With this patch it's now a compile error, so these functions are now hidden behind an #ifndef CONFIG_SLOB. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com> Tested-by: Marco Elver <elver@google.com> # kfence Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: <kasan-dev@googlegroups.com>
2022-01-06mm/kfence: Convert kfence_guarded_alloc() to struct slabVlastimil Babka
The function sets some fields that are being moved from struct page to struct slab so it needs to be converted. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Tested-by: Marco Elver <elver@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: <kasan-dev@googlegroups.com>
2022-01-06mm/kasan: Convert to struct folio and struct slabMatthew Wilcox (Oracle)
KASAN accesses some slab related struct page fields so we need to convert it to struct slab. Some places are a bit simplified thanks to kasan_addr_to_slab() encapsulating the PageSlab flag check through virt_to_slab(). When resolving object address to either a real slab or a large kmalloc, use struct folio as the intermediate type for testing the slab flag to avoid unnecessary implicit compound_head(). [ vbabka@suse.cz: use struct folio, adjust to differences in previous patches ] Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Reviewed-by: Roman Gushchin <guro@fb.com> Tested-by: Hyeongogn Yoo <42.hyeyoo@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: <kasan-dev@googlegroups.com>
2022-01-06mm/slob: Convert SLOB to use struct slab and struct folioMatthew Wilcox (Oracle)
Use struct slab throughout the slob allocator. Where non-slab page can appear use struct folio instead of struct page. [ vbabka@suse.cz: don't introduce wrappers for PageSlobFree in mm/slab.h just for the single callers being wrappers in mm/slob.c ] [ Hyeonggon Yoo <42.hyeyoo@gmail.com>: fix NULL pointer deference ] Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06mm/memcg: Convert slab objcgs from struct page to struct slabVlastimil Babka
page->memcg_data is used with MEMCG_DATA_OBJCGS flag only for slab pages so convert all the related infrastructure to struct slab. Also use struct folio instead of struct page when resolving object pointers. This is not just mechanistic changing of types and names. Now in mem_cgroup_from_obj() we use folio_test_slab() to decide if we interpret the folio as a real slab instead of a large kmalloc, instead of relying on MEMCG_DATA_OBJCGS bit that used to be checked in page_objcgs_check(). Similarly in memcg_slab_free_hook() where we can encounter kmalloc_large() pages (here the folio slab flag check is implied by virt_to_slab()). As a result, page_objcgs_check() can be dropped instead of converted. To avoid include cycles, move the inline definition of slab_objcgs() from memcontrol.h to mm/slab.h. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <cgroups@vger.kernel.org>
2022-01-06mm: Convert struct page to struct slab in functions used by other subsystemsVlastimil Babka
KASAN, KFENCE and memcg interact with SLAB or SLUB internals through functions nearest_obj(), obj_to_index() and objs_per_slab() that use struct page as parameter. This patch converts it to struct slab including all callers, through a coccinelle semantic patch. // Options: --include-headers --no-includes --smpl-spacing include/linux/slab_def.h include/linux/slub_def.h mm/slab.h mm/kasan/*.c mm/kfence/kfence_test.c mm/memcontrol.c mm/slab.c mm/slub.c // Note: needs coccinelle 1.1.1 to avoid breaking whitespace @@ @@ -objs_per_slab_page( +objs_per_slab( ... ) { ... } @@ @@ -objs_per_slab_page( +objs_per_slab( ... ) @@ identifier fn =~ "obj_to_index|objs_per_slab"; @@ fn(..., - const struct page *page + const struct slab *slab ,...) { <... ( - page_address(page) + slab_address(slab) | - page + slab ) ...> } @@ identifier fn =~ "nearest_obj"; @@ fn(..., - struct page *page + const struct slab *slab ,...) { <... ( - page_address(page) + slab_address(slab) | - page + slab ) ...> } @@ identifier fn =~ "nearest_obj|obj_to_index|objs_per_slab"; expression E; @@ fn(..., ( - slab_page(E) + E | - virt_to_page(E) + virt_to_slab(E) | - virt_to_head_page(E) + virt_to_slab(E) | - page + page_slab(page) ) ,...) Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Reviewed-by: Roman Gushchin <guro@fb.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Julia Lawall <julia.lawall@inria.fr> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: <kasan-dev@googlegroups.com> Cc: <cgroups@vger.kernel.org>
2022-01-06mm/slab: Finish struct page to struct slab conversionVlastimil Babka
Change cache_free_alien() to use slab_nid(virt_to_slab()). Otherwise just update of comments and some remaining variable names. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06mm/slab: Convert most struct page to struct slab by spatchVlastimil Babka
The majority of conversion from struct page to struct slab in SLAB internals can be delegated to a coccinelle semantic patch. This includes renaming of variables with 'page' in name to 'slab', and similar. Big thanks to Julia Lawall and Luis Chamberlain for help with coccinelle. // Options: --include-headers --no-includes --smpl-spacing mm/slab.c // Note: needs coccinelle 1.1.1 to avoid breaking whitespace, and ocaml for the // embedded script // build list of functions for applying the next rule @initialize:ocaml@ @@ let ok_function p = not (List.mem (List.hd p).current_element ["kmem_getpages";"kmem_freepages"]) // convert the type in selected functions @@ position p : script:ocaml() { ok_function p }; @@ - struct page@p + struct slab @@ @@ -PageSlabPfmemalloc(page) +slab_test_pfmemalloc(slab) @@ @@ -ClearPageSlabPfmemalloc(page) +slab_clear_pfmemalloc(slab) @@ @@ obj_to_index( ..., - page + slab_page(slab) ,...) // for all functions, change any "struct slab *page" parameter to "struct slab // *slab" in the signature, and generally all occurences of "page" to "slab" in // the body - with some special cases. @@ identifier fn; expression E; @@ fn(..., - struct slab *page + struct slab *slab ,...) { <... ( - int page_node; + int slab_node; | - page_node + slab_node | - page_slab(page) + slab | - page_address(page) + slab_address(slab) | - page_size(page) + slab_size(slab) | - page_to_nid(page) + slab_nid(slab) | - virt_to_head_page(E) + virt_to_slab(E) | - page + slab ) ...> } // rename a function parameter @@ identifier fn; expression E; @@ fn(..., - int page_node + int slab_node ,...) { <... - page_node + slab_node ...> } // functions converted by previous rules that were temporarily called using // slab_page(E) so we want to remove the wrapper now that they accept struct // slab ptr directly @@ identifier fn =~ "index_to_obj"; expression E; @@ fn(..., - slab_page(E) + E ,...) // functions that were returning struct page ptr and now will return struct // slab ptr, including slab_page() wrapper removal @@ identifier fn =~ "cache_grow_begin|get_valid_first_slab|get_first_slab"; expression E; @@ fn(...) { <... - slab_page(E) + E ...> } // rename any former struct page * declarations @@ @@ struct slab * -page +slab ; // all functions (with exceptions) with a local "struct slab *page" variable // that will be renamed to "struct slab *slab" @@ identifier fn !~ "kmem_getpages|kmem_freepages"; expression E; @@ fn(...) { <... ( - page_slab(page) + slab | - page_to_nid(page) + slab_nid(slab) | - kasan_poison_slab(page) + kasan_poison_slab(slab_page(slab)) | - page_address(page) + slab_address(slab) | - page_size(page) + slab_size(slab) | - page->pages + slab->slabs | - page = virt_to_head_page(E) + slab = virt_to_slab(E) | - virt_to_head_page(E) + virt_to_slab(E) | - page + slab ) ...> } Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Julia Lawall <julia.lawall@inria.fr> Cc: Luis Chamberlain <mcgrof@kernel.org>
2022-01-06mm/slab: Convert kmem_getpages() and kmem_freepages() to struct slabVlastimil Babka
These functions sit at the boundary to page allocator. Also use folio internally to avoid extra compound_head() when dealing with page flags. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
2022-01-06mm/slub: Finish struct page to struct slab conversionVlastimil Babka
Update comments mentioning pages to mention slabs where appropriate. Also some goto labels. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com>
2022-01-06mm/slub: Convert most struct page to struct slab by spatchVlastimil Babka
The majority of conversion from struct page to struct slab in SLUB internals can be delegated to a coccinelle semantic patch. This includes renaming of variables with 'page' in name to 'slab', and similar. Big thanks to Julia Lawall and Luis Chamberlain for help with coccinelle. // Options: --include-headers --no-includes --smpl-spacing include/linux/slub_def.h mm/slub.c // Note: needs coccinelle 1.1.1 to avoid breaking whitespace, and ocaml for the // embedded script // build list of functions to exclude from applying the next rule @initialize:ocaml@ @@ let ok_function p = not (List.mem (List.hd p).current_element ["nearest_obj";"obj_to_index";"objs_per_slab_page";"__slab_lock";"__slab_unlock";"free_nonslab_page";"kmalloc_large_node"]) // convert the type from struct page to struct page in all functions except the // list from previous rule // this also affects struct kmem_cache_cpu, but that's ok @@ position p : script:ocaml() { ok_function p }; @@ - struct page@p + struct slab // in struct kmem_cache_cpu, change the name from page to slab // the type was already converted by the previous rule @@ @@ struct kmem_cache_cpu { ... -struct slab *page; +struct slab *slab; ... } // there are many places that use c->page which is now c->slab after the // previous rule @@ struct kmem_cache_cpu *c; @@ -c->page +c->slab @@ @@ struct kmem_cache { ... - unsigned int cpu_partial_pages; + unsigned int cpu_partial_slabs; ... } @@ struct kmem_cache *s; @@ - s->cpu_partial_pages + s->cpu_partial_slabs @@ @@ static void - setup_page_debug( + setup_slab_debug( ...) {...} @@ @@ - setup_page_debug( + setup_slab_debug( ...); // for all functions (with exceptions), change any "struct slab *page" // parameter to "struct slab *slab" in the signature, and generally all // occurences of "page" to "slab" in the body - with some special cases. @@ identifier fn !~ "free_nonslab_page|obj_to_index|objs_per_slab_page|nearest_obj"; @@ fn(..., - struct slab *page + struct slab *slab ,...) { <... - page + slab ...> } // similar to previous but the param is called partial_page @@ identifier fn; @@ fn(..., - struct slab *partial_page + struct slab *partial_slab ,...) { <... - partial_page + partial_slab ...> } // similar to previous but for functions that take pointer to struct page ptr @@ identifier fn; @@ fn(..., - struct slab **ret_page + struct slab **ret_slab ,...) { <... - ret_page + ret_slab ...> } // functions converted by previous rules that were temporarily called using // slab_page(E) so we want to remove the wrapper now that they accept struct // slab ptr directly @@ identifier fn =~ "slab_free|do_slab_free"; expression E; @@ fn(..., - slab_page(E) + E ,...) // similar to previous but for another pattern @@ identifier fn =~ "slab_pad_check|check_object"; @@ fn(..., - folio_page(folio, 0) + slab ,...) // functions that were returning struct page ptr and now will return struct // slab ptr, including slab_page() wrapper removal @@ identifier fn =~ "allocate_slab|new_slab"; expression E; @@ static -struct slab * +struct slab * fn(...) { <... - slab_page(E) + E ...> } // rename any former struct page * declarations @@ @@ struct slab * ( - page + slab | - partial_page + partial_slab | - oldpage + oldslab ) ; // this has to be separate from previous rule as page and page2 appear at the // same line @@ @@ struct slab * -page2 +slab2 ; // similar but with initial assignment @@ expression E; @@ struct slab * ( - page + slab | - flush_page + flush_slab | - discard_page + slab_to_discard | - page_to_unfreeze + slab_to_unfreeze ) = E; // convert most of struct page to struct slab usage inside functions (with // exceptions), including specific variable renames @@ identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node"; expression E; @@ fn(...) { <... ( - int pages; + int slabs; | - int pages = E; + int slabs = E; | - page + slab | - flush_page + flush_slab | - partial_page + partial_slab | - oldpage->pages + oldslab->slabs | - oldpage + oldslab | - unsigned int nr_pages; + unsigned int nr_slabs; | - nr_pages + nr_slabs | - unsigned int partial_pages = E; + unsigned int partial_slabs = E; | - partial_pages + partial_slabs ) ...> } // this has to be split out from the previous rule so that lines containing // multiple matching changes will be fully converted @@ identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node"; @@ fn(...) { <... ( - slab->pages + slab->slabs | - pages + slabs | - page2 + slab2 | - discard_page + slab_to_discard | - page_to_unfreeze + slab_to_unfreeze ) ...> } // after we simply changed all occurences of page to slab, some usages need // adjustment for slab-specific functions, or use slab_page() wrapper @@ identifier fn !~ "nearest_obj|obj_to_index|objs_per_slab_page|__slab_(un)*lock|__free_slab|free_nonslab_page|kmalloc_large_node"; @@ fn(...) { <... ( - page_slab(slab) + slab | - kasan_poison_slab(slab) + kasan_poison_slab(slab_page(slab)) | - page_address(slab) + slab_address(slab) | - page_size(slab) + slab_size(slab) | - PageSlab(slab) + folio_test_slab(slab_folio(slab)) | - page_to_nid(slab) + slab_nid(slab) | - compound_order(slab) + slab_order(slab) ) ...> } Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Roman Gushchin <guro@fb.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Tested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Julia Lawall <julia.lawall@inria.fr> Cc: Luis Chamberlain <mcgrof@kernel.org>