x86 microcode: revert some work_on_cpu (6f66cbc6) · Commits · 戴 / test

Revert part of ("x86: cpumask: use work_on_cpu in arch/x86/kernel/microcode_core.c") That change is causing only one Intel CPU's microcode to be updated e.g. microcode: CPU3 updated from revision 0x9 to 0x17, date = 2005-04-22 where before it announced that also for CPU0 and CPU1 and CPU2. We cannot use work_on_cpu() in the CONFIG_MICROCODE_OLD_INTERFACE code, because Intel's request_microcode_user() involves a copy_from_user() from /sbin/microcode_ctl, which therefore needs to be on that CPU at the time. Signed-off-by:

Hugh Dickins <hugh@veritas.com> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/kernel/microcode_core.c

+11 −22

Original line number	Diff line number	Diff line
		@@ -108,40 +108,29 @@ struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
		EXPORT_SYMBOL_GPL(ucode_cpu_info);

		#ifdef CONFIG_MICROCODE_OLD_INTERFACE
		struct update_for_cpu {
		const void __user *buf;
		size_t size;
		};

		static long update_for_cpu(void *_ufc)
		{
		struct update_for_cpu *ufc = _ufc;
		int error;

		error = microcode_ops->request_microcode_user(smp_processor_id(),
		ufc->buf, ufc->size);
		if (error < 0)
		return error;
		if (!error)
		microcode_ops->apply_microcode(smp_processor_id());
		return error;
		}

		static int do_microcode_update(const void __user *buf, size_t size)
		{
		cpumask_t old;
		int error = 0;
		int cpu;
		struct update_for_cpu ufc = { .buf = buf, .size = size };

		old = current->cpus_allowed;

		for_each_online_cpu(cpu) {
		struct ucode_cpu_info *uci = ucode_cpu_info + cpu;

		if (!uci->valid)
		continue;
		error = work_on_cpu(cpu, update_for_cpu, &ufc);

		set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
		error = microcode_ops->request_microcode_user(cpu, buf, size);
		if (error < 0)
		break;
		goto out;
		if (!error)
		microcode_ops->apply_microcode(cpu);
		}
		out:
		set_cpus_allowed_ptr(current, &old);
		return error;
		}

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