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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /arch/x86/lib/msr-smp.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'arch/x86/lib/msr-smp.c')
-rw-r--r--arch/x86/lib/msr-smp.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/arch/x86/lib/msr-smp.c b/arch/x86/lib/msr-smp.c
new file mode 100644
index 000000000..7b6cfc2c0
--- /dev/null
+++ b/arch/x86/lib/msr-smp.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/export.h>
+#include <linux/preempt.h>
+#include <linux/smp.h>
+#include <linux/completion.h>
+#include <asm/msr.h>
+
+static void __rdmsr_on_cpu(void *info)
+{
+ struct msr_info *rv = info;
+ struct msr *reg;
+
+ if (rv->msrs)
+ reg = this_cpu_ptr(rv->msrs);
+ else
+ reg = &rv->reg;
+
+ rdmsrq(rv->msr_no, reg->q);
+}
+
+static void __wrmsr_on_cpu(void *info)
+{
+ struct msr_info *rv = info;
+ struct msr *reg;
+
+ if (rv->msrs)
+ reg = this_cpu_ptr(rv->msrs);
+ else
+ reg = &rv->reg;
+
+ wrmsrq(rv->msr_no, reg->q);
+}
+
+int rdmsrq_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+ int err;
+ struct msr_info rv;
+
+ memset(&rv, 0, sizeof(rv));
+
+ rv.msr_no = msr_no;
+ err = smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 1);
+ *q = rv.reg.q;
+
+ return err;
+}
+EXPORT_SYMBOL(rdmsrq_on_cpu);
+
+int wrmsrq_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+ int err;
+ struct msr_info rv;
+
+ memset(&rv, 0, sizeof(rv));
+
+ rv.msr_no = msr_no;
+ rv.reg.q = q;
+
+ err = smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 1);
+
+ return err;
+}
+EXPORT_SYMBOL(wrmsrq_on_cpu);
+
+static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no,
+ struct msr __percpu *msrs,
+ void (*msr_func) (void *info))
+{
+ struct msr_info rv;
+ int this_cpu;
+
+ memset(&rv, 0, sizeof(rv));
+
+ rv.msrs = msrs;
+ rv.msr_no = msr_no;
+
+ this_cpu = get_cpu();
+
+ if (cpumask_test_cpu(this_cpu, mask))
+ msr_func(&rv);
+
+ smp_call_function_many(mask, msr_func, &rv, 1);
+ put_cpu();
+}
+
+/* rdmsr on a bunch of CPUs
+ *
+ * @mask: which CPUs
+ * @msr_no: which MSR
+ * @msrs: array of MSR values
+ *
+ */
+void rdmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
+{
+ __rwmsr_on_cpus(mask, msr_no, msrs, __rdmsr_on_cpu);
+}
+EXPORT_SYMBOL(rdmsr_on_cpus);
+
+/*
+ * wrmsr on a bunch of CPUs
+ *
+ * @mask: which CPUs
+ * @msr_no: which MSR
+ * @msrs: array of MSR values
+ *
+ */
+void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr __percpu *msrs)
+{
+ __rwmsr_on_cpus(mask, msr_no, msrs, __wrmsr_on_cpu);
+}
+EXPORT_SYMBOL(wrmsr_on_cpus);
+
+struct msr_info_completion {
+ struct msr_info msr;
+ struct completion done;
+};
+
+/* These "safe" variants are slower and should be used when the target MSR
+ may not actually exist. */
+static void __rdmsr_safe_on_cpu(void *info)
+{
+ struct msr_info_completion *rv = info;
+
+ rv->msr.err = rdmsrq_safe(rv->msr.msr_no, &rv->msr.reg.q);
+ complete(&rv->done);
+}
+
+static void __wrmsr_safe_on_cpu(void *info)
+{
+ struct msr_info *rv = info;
+
+ rv->err = wrmsrq_safe(rv->msr_no, rv->reg.q);
+}
+
+int wrmsrq_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 q)
+{
+ int err;
+ struct msr_info rv;
+
+ memset(&rv, 0, sizeof(rv));
+
+ rv.msr_no = msr_no;
+ rv.reg.q = q;
+
+ err = smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 1);
+
+ return err ? err : rv.err;
+}
+EXPORT_SYMBOL(wrmsrq_safe_on_cpu);
+
+int rdmsrq_safe_on_cpu(unsigned int cpu, u32 msr_no, u64 *q)
+{
+ struct msr_info_completion rv;
+ call_single_data_t csd;
+ int err;
+
+ INIT_CSD(&csd, __rdmsr_safe_on_cpu, &rv);
+
+ memset(&rv, 0, sizeof(rv));
+ init_completion(&rv.done);
+ rv.msr.msr_no = msr_no;
+
+ err = smp_call_function_single_async(cpu, &csd);
+ if (!err) {
+ wait_for_completion(&rv.done);
+ err = rv.msr.err;
+ }
+ *q = rv.msr.reg.q;
+
+ return err;
+}
+EXPORT_SYMBOL(rdmsrq_safe_on_cpu);
+
+/*
+ * These variants are significantly slower, but allows control over
+ * the entire 32-bit GPR set.
+ */
+static void __rdmsr_safe_regs_on_cpu(void *info)
+{
+ struct msr_regs_info *rv = info;
+
+ rv->err = rdmsr_safe_regs(rv->regs);
+}
+
+static void __wrmsr_safe_regs_on_cpu(void *info)
+{
+ struct msr_regs_info *rv = info;
+
+ rv->err = wrmsr_safe_regs(rv->regs);
+}
+
+int rdmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
+{
+ int err;
+ struct msr_regs_info rv;
+
+ rv.regs = regs;
+ rv.err = -EIO;
+ err = smp_call_function_single(cpu, __rdmsr_safe_regs_on_cpu, &rv, 1);
+
+ return err ? err : rv.err;
+}
+EXPORT_SYMBOL(rdmsr_safe_regs_on_cpu);
+
+int wrmsr_safe_regs_on_cpu(unsigned int cpu, u32 regs[8])
+{
+ int err;
+ struct msr_regs_info rv;
+
+ rv.regs = regs;
+ rv.err = -EIO;
+ err = smp_call_function_single(cpu, __wrmsr_safe_regs_on_cpu, &rv, 1);
+
+ return err ? err : rv.err;
+}
+EXPORT_SYMBOL(wrmsr_safe_regs_on_cpu);