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Date: Fri, 28 Oct 2022 16:26:35 +0200
From: Borislav Petkov <bp@...en8.de>
To: Ashok Raj <ashok.raj@...el.com>
Cc: X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 2/5] x86/microcode: Simplify init path even more
From: Borislav Petkov <bp@...e.de>
Get rid of all the IPI-sending functions and their wrappers and use
those which are supposed to be called on each CPU.
Thus:
- microcode_init_cpu() gets called on each CPU on init, applying any new
microcode that the driver might've found on the filesystem.
- mc_cpu_starting() simply tries to apply cached microcode as this is
the cpuhp starting callback which gets called on CPU resume too.
Even if the driver init function is a late initcall, there is no
filesystem by then (not even a hdd driver has been loaded yet) so a new
firmware load attempt cannot simply be done.
It is pointless anyway - for that there's late loading if one really
needs it.
Signed-off-by: Borislav Petkov <bp@...e.de>
---
arch/x86/kernel/cpu/microcode/core.c | 120 ++++-----------------------
1 file changed, 16 insertions(+), 104 deletions(-)
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 4c222e667567..63f7678743be 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -319,60 +319,6 @@ void reload_early_microcode(void)
}
}
-static void collect_cpu_info_local(void *arg)
-{
- struct cpu_info_ctx *ctx = arg;
-
- ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(),
- ctx->cpu_sig);
-}
-
-static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig)
-{
- struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 };
- int ret;
-
- ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1);
- if (!ret)
- ret = ctx.err;
-
- return ret;
-}
-
-static int collect_cpu_info(int cpu)
-{
- struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
- int ret;
-
- memset(uci, 0, sizeof(*uci));
-
- ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig);
- if (!ret)
- uci->valid = 1;
-
- return ret;
-}
-
-static void apply_microcode_local(void *arg)
-{
- enum ucode_state *err = arg;
-
- *err = microcode_ops->apply_microcode(smp_processor_id());
-}
-
-static int apply_microcode_on_target(int cpu)
-{
- enum ucode_state err;
- int ret;
-
- ret = smp_call_function_single(cpu, apply_microcode_local, &err, 1);
- if (!ret) {
- if (err == UCODE_ERROR)
- ret = 1;
- }
- return ret;
-}
-
/* fake device for request_firmware */
static struct platform_device *microcode_pdev;
@@ -458,7 +404,7 @@ static int __reload_late(void *info)
* below.
*/
if (cpumask_first(topology_sibling_cpumask(cpu)) == cpu)
- apply_microcode_local(&err);
+ err = microcode_ops->apply_microcode(cpu);
else
goto wait_for_siblings;
@@ -480,7 +426,7 @@ static int __reload_late(void *info)
* revision.
*/
if (cpumask_first(topology_sibling_cpumask(cpu)) != cpu)
- apply_microcode_local(&err);
+ err = microcode_ops->apply_microcode(cpu);
return ret;
}
@@ -589,51 +535,15 @@ static void microcode_fini_cpu(int cpu)
microcode_ops->microcode_fini_cpu(cpu);
}
-static enum ucode_state microcode_resume_cpu(int cpu)
-{
- if (apply_microcode_on_target(cpu))
- return UCODE_ERROR;
-
- pr_debug("CPU%d updated upon resume\n", cpu);
-
- return UCODE_OK;
-}
-
-static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
-{
- struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
- enum ucode_state ustate;
-
- if (uci->valid)
- return UCODE_OK;
-
- if (collect_cpu_info(cpu))
- return UCODE_ERROR;
-
- /* --dimm. Trigger a delayed update? */
- if (system_state != SYSTEM_RUNNING)
- return UCODE_NFOUND;
-
- ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev, refresh_fw);
- if (ustate == UCODE_NEW) {
- pr_debug("CPU%d updated upon init\n", cpu);
- apply_microcode_on_target(cpu);
- }
-
- return ustate;
-}
-
-static enum ucode_state microcode_update_cpu(int cpu)
+static enum ucode_state microcode_init_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
- /* Refresh CPU microcode revision after resume. */
- collect_cpu_info(cpu);
+ memset(uci, 0, sizeof(*uci));
- if (uci->valid)
- return microcode_resume_cpu(cpu);
+ microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig);
- return microcode_init_cpu(cpu, false);
+ return microcode_ops->apply_microcode(cpu);
}
/**
@@ -651,14 +561,14 @@ void microcode_bsp_resume(void)
}
static struct syscore_ops mc_syscore_ops = {
- .resume = microcode_bsp_resume,
+ .resume = microcode_bsp_resume,
};
static int mc_cpu_starting(unsigned int cpu)
{
- microcode_update_cpu(cpu);
- pr_debug("CPU%d added\n", cpu);
- return 0;
+ enum ucode_state err = microcode_ops->apply_microcode(cpu);
+
+ return err == UCODE_ERROR;
}
static int mc_cpu_online(unsigned int cpu)
@@ -688,11 +598,13 @@ static int mc_cpu_down_prep(unsigned int cpu)
static void setup_online_cpu(struct work_struct *work)
{
int cpu = smp_processor_id();
- struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
-
- memset(uci, 0, sizeof(*uci));
+ enum ucode_state err;
- microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig);
+ err = microcode_init_cpu(cpu);
+ if (err == UCODE_ERROR) {
+ pr_err("Error applying microcode on CPU%d\n", cpu);
+ return;
+ }
mc_cpu_online(cpu);
}
--
2.35.1
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