From 0d6526f82c3cdefcca47f73f5fc08dc6f335eac6 Mon Sep 17 00:00:00 2001 From: Tim Chen Date: Mon, 21 Sep 2026 17:37:22 -0700 Subject: sched/cache: Keep nr_pref_llc_running in the runnable domain, to fix LLC mis-scheduling bug alb_break_llc() decides whether to break LLC preference during active load balance. It does so by testing that every runnable fair task on the source rq prefers its LLC: env->src_rq->nr_pref_llc_running == env->src_rq->cfs.h_nr_runnable But the two counters cover different sets. nr_pref_llc_running is updated in account_llc_enqueue()/account_llc_dequeue(), next to cfs_rq->nr_queued, so it follows queued tasks. h_nr_runnable is updated in set_delayed()/ clear_delayed() and drops delay-dequeued tasks. So under DELAY_DEQUEUE, a preferring task that goes to sleep stays counted in nr_pref_llc_running while h_nr_runnable falls. The equality then breaks, alb_break_llc() returns false, and active balance is free to pull a task off its preferred LLC. Active balance only moves runnable tasks, and this is the only LLC check it consults: once the stopper runs, LBF_ACTIVE_LB skips the per-task test in can_migrate_task(). The runnable set is the one we want. Fix it on the counter side. A task should be counted in nr_pref_llc_running exactly while it is both queued on its preferred LLC (pref_llc_queued) and runnable (!sched_delayed). Define that membership once in task_pref_llc_runnable(), and adjust the counter only through pref_llc_running_inc()/pref_llc_running_dec() from the four sites that change either input: account_llc_enqueue(), account_llc_dequeue(), set_delayed() and clear_delayed(). Gating every update on the same predicate keeps the delay, wake and dequeue paths from double-counting or underflowing; see the comments at those sites for the ordering. nr_llc_running and sd->llc_counts are not touched and stay on queued semantics. Fixes: 714059f79ff0 ("sched/cache: Handle moving single tasks to/from their preferred LLC") Closes: https://lore.kernel.org/lkml/20260827135000.735138-1-zhanxusheng@xiaomi.com/ Reported-by: Zhan Xusheng Suggested-by: Chen Yu Signed-off-by: Tim Chen Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Ingo Molnar Reviewed-by: Kayra Cizmeci Cc: # v7.2.x Link: https://patch.msgid.link/06af61afedac32e6477f57feb4d658f6c411c3af.1790035273.git.tim.c.chen@linux.intel.com --- crypto/mldsa.c | 201 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 201 insertions(+) create mode 100644 crypto/mldsa.c (limited to 'crypto/mldsa.c') diff --git a/crypto/mldsa.c b/crypto/mldsa.c new file mode 100644 index 000000000..d8de082cc --- /dev/null +++ b/crypto/mldsa.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * crypto_sig wrapper around ML-DSA library. + */ +#include +#include +#include +#include + +struct crypto_mldsa_ctx { + u8 pk[MAX(MAX(MLDSA44_PUBLIC_KEY_SIZE, + MLDSA65_PUBLIC_KEY_SIZE), + MLDSA87_PUBLIC_KEY_SIZE)]; + unsigned int pk_len; + enum mldsa_alg strength; + bool key_set; +}; + +static int crypto_mldsa_sign(struct crypto_sig *tfm, + const void *msg, unsigned int msg_len, + void *sig, unsigned int sig_len) +{ + return -EOPNOTSUPP; +} + +static int crypto_mldsa_verify(struct crypto_sig *tfm, + const void *sig, unsigned int sig_len, + const void *msg, unsigned int msg_len) +{ + const struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + if (unlikely(!ctx->key_set)) + return -EINVAL; + + return mldsa_verify(ctx->strength, sig, sig_len, msg, msg_len, + ctx->pk, ctx->pk_len); +} + +static unsigned int crypto_mldsa_key_size(struct crypto_sig *tfm) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + switch (ctx->strength) { + case MLDSA44: + return MLDSA44_PUBLIC_KEY_SIZE; + case MLDSA65: + return MLDSA65_PUBLIC_KEY_SIZE; + case MLDSA87: + return MLDSA87_PUBLIC_KEY_SIZE; + default: + WARN_ON_ONCE(1); + return 0; + } +} + +static int crypto_mldsa_set_pub_key(struct crypto_sig *tfm, + const void *key, unsigned int keylen) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + unsigned int expected_len = crypto_mldsa_key_size(tfm); + + if (keylen != expected_len) + return -EINVAL; + + ctx->pk_len = keylen; + memcpy(ctx->pk, key, keylen); + ctx->key_set = true; + return 0; +} + +static int crypto_mldsa_set_priv_key(struct crypto_sig *tfm, + const void *key, unsigned int keylen) +{ + return -EOPNOTSUPP; +} + +static unsigned int crypto_mldsa_max_size(struct crypto_sig *tfm) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + switch (ctx->strength) { + case MLDSA44: + return MLDSA44_SIGNATURE_SIZE; + case MLDSA65: + return MLDSA65_SIGNATURE_SIZE; + case MLDSA87: + return MLDSA87_SIGNATURE_SIZE; + default: + WARN_ON_ONCE(1); + return 0; + } +} + +static int crypto_mldsa44_alg_init(struct crypto_sig *tfm) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + ctx->strength = MLDSA44; + ctx->key_set = false; + return 0; +} + +static int crypto_mldsa65_alg_init(struct crypto_sig *tfm) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + ctx->strength = MLDSA65; + ctx->key_set = false; + return 0; +} + +static int crypto_mldsa87_alg_init(struct crypto_sig *tfm) +{ + struct crypto_mldsa_ctx *ctx = crypto_sig_ctx(tfm); + + ctx->strength = MLDSA87; + ctx->key_set = false; + return 0; +} + +static void crypto_mldsa_alg_exit(struct crypto_sig *tfm) +{ +} + +static struct sig_alg crypto_mldsa_algs[] = { + { + .sign = crypto_mldsa_sign, + .verify = crypto_mldsa_verify, + .set_pub_key = crypto_mldsa_set_pub_key, + .set_priv_key = crypto_mldsa_set_priv_key, + .key_size = crypto_mldsa_key_size, + .max_size = crypto_mldsa_max_size, + .init = crypto_mldsa44_alg_init, + .exit = crypto_mldsa_alg_exit, + .base.cra_name = "mldsa44", + .base.cra_driver_name = "mldsa44-lib", + .base.cra_ctxsize = sizeof(struct crypto_mldsa_ctx), + .base.cra_module = THIS_MODULE, + .base.cra_priority = 5000, + }, { + .sign = crypto_mldsa_sign, + .verify = crypto_mldsa_verify, + .set_pub_key = crypto_mldsa_set_pub_key, + .set_priv_key = crypto_mldsa_set_priv_key, + .key_size = crypto_mldsa_key_size, + .max_size = crypto_mldsa_max_size, + .init = crypto_mldsa65_alg_init, + .exit = crypto_mldsa_alg_exit, + .base.cra_name = "mldsa65", + .base.cra_driver_name = "mldsa65-lib", + .base.cra_ctxsize = sizeof(struct crypto_mldsa_ctx), + .base.cra_module = THIS_MODULE, + .base.cra_priority = 5000, + }, { + .sign = crypto_mldsa_sign, + .verify = crypto_mldsa_verify, + .set_pub_key = crypto_mldsa_set_pub_key, + .set_priv_key = crypto_mldsa_set_priv_key, + .key_size = crypto_mldsa_key_size, + .max_size = crypto_mldsa_max_size, + .init = crypto_mldsa87_alg_init, + .exit = crypto_mldsa_alg_exit, + .base.cra_name = "mldsa87", + .base.cra_driver_name = "mldsa87-lib", + .base.cra_ctxsize = sizeof(struct crypto_mldsa_ctx), + .base.cra_module = THIS_MODULE, + .base.cra_priority = 5000, + }, +}; + +static int __init mldsa_init(void) +{ + int ret, i; + + for (i = 0; i < ARRAY_SIZE(crypto_mldsa_algs); i++) { + ret = crypto_register_sig(&crypto_mldsa_algs[i]); + if (ret < 0) + goto error; + } + return 0; + +error: + pr_err("Failed to register (%d)\n", ret); + for (i--; i >= 0; i--) + crypto_unregister_sig(&crypto_mldsa_algs[i]); + return ret; +} +module_init(mldsa_init); + +static void mldsa_exit(void) +{ + for (int i = 0; i < ARRAY_SIZE(crypto_mldsa_algs); i++) + crypto_unregister_sig(&crypto_mldsa_algs[i]); +} +module_exit(mldsa_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Crypto API support for ML-DSA signature verification"); +MODULE_ALIAS_CRYPTO("mldsa44"); +MODULE_ALIAS_CRYPTO("mldsa65"); +MODULE_ALIAS_CRYPTO("mldsa87"); -- cgit v1.3.1