From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: linux-kernel@vger.kernel.org
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
linux-mm@kvack.org, Masami Hiramatsu <mhiramat@kernel.org>,
Andi Kleen <ak@linux.intel.com>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)),
"H. Peter Anvin" <hpa@zytor.com>,
Andy Lutomirski <luto@kernel.org>,
"Paul E. McKenney" <paulmck@kernel.org>,
Marco Elver <elver@google.com>, Babu Moger <Babu.Moger@amd.com>,
Brian Gerst <brgerst@gmail.com>, Nayna Jain <nayna@linux.ibm.com>
Subject: [PATCH v5 3/6] arch/x86: Implement text_alloc() and text_free()
Date: Fri, 24 Jul 2020 08:05:50 +0300 [thread overview]
Message-ID: <20200724050553.1724168-4-jarkko.sakkinen@linux.intel.com> (raw)
In-Reply-To: <20200724050553.1724168-1-jarkko.sakkinen@linux.intel.com>
Implement text_alloc() and text_free() with with the vmalloc API. These can
be used to allocate pages for trampoline code without relying on the module
loader code.
Cc: linux-mm@kvack.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
arch/x86/Kconfig | 3 +++
arch/x86/kernel/Makefile | 1 +
arch/x86/kernel/text_alloc.c | 41 ++++++++++++++++++++++++++++++++++++
3 files changed, 45 insertions(+)
create mode 100644 arch/x86/kernel/text_alloc.c
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0dea7fdd7a00..a4ee5d1300f6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2035,6 +2035,9 @@ config KEXEC_FILE
config ARCH_HAS_KEXEC_PURGATORY
def_bool KEXEC_FILE
+config ARCH_HAS_TEXT_ALLOC
+ def_bool y
+
config KEXEC_SIG
bool "Verify kernel signature during kexec_file_load() syscall"
depends on KEXEC_FILE
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index e77261db2391..fa1415424ae3 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -68,6 +68,7 @@ obj-y += tsc.o tsc_msr.o io_delay.o rtc.o
obj-y += pci-iommu_table.o
obj-y += resource.o
obj-y += irqflags.o
+obj-y += text_alloc.o
obj-y += process.o
obj-y += fpu/
diff --git a/arch/x86/kernel/text_alloc.c b/arch/x86/kernel/text_alloc.c
new file mode 100644
index 000000000000..f31c2d82c258
--- /dev/null
+++ b/arch/x86/kernel/text_alloc.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Kernel module help for x86.
+ * Copyright (C) 2001 Rusty Russell.
+ */
+
+#include <linux/kasan.h>
+#include <linux/mm.h>
+#include <linux/moduleloader.h>
+#include <linux/vmalloc.h>
+#include <asm/setup.h>
+
+void *text_alloc(unsigned long size)
+{
+ void *p;
+
+ if (PAGE_ALIGN(size) > MODULES_LEN)
+ return NULL;
+
+ p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR, MODULES_END,
+ GFP_KERNEL, PAGE_KERNEL, 0, NUMA_NO_NODE,
+ __builtin_return_address(0));
+
+ if (p && (kasan_module_alloc(p, size) < 0)) {
+ vfree(p);
+ return NULL;
+ }
+
+ return p;
+}
+
+void text_free(void *region)
+{
+ /*
+ * This memory may be RO, and freeing RO memory in an interrupt is not
+ * supported by vmalloc.
+ */
+ lockdep_assert_irqs_enabled();
+
+ vfree(region);
+}
--
2.25.1
next prev parent reply other threads:[~2020-07-24 5:06 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-24 5:05 [PATCH v5 0/6] arch/x86: kprobes: Remove MODULES dependency Jarkko Sakkinen
2020-07-24 5:05 ` [PATCH v5 1/6] kprobes: Remove dependency to the module_mutex Jarkko Sakkinen
2020-07-24 9:13 ` Ingo Molnar
2020-07-25 2:36 ` Jarkko Sakkinen
2020-07-24 9:17 ` Ingo Molnar
2020-07-25 3:01 ` Jarkko Sakkinen
2020-07-25 10:21 ` Ingo Molnar
2020-07-28 7:34 ` Masami Hiramatsu
2020-07-28 12:29 ` [tip: perf/core] kprobes: Remove unnecessary module_mutex locking from kprobe_optimizer() tip-bot2 for Masami Hiramatsu
2020-08-17 21:22 ` [PATCH v5 1/6] kprobes: Remove dependency to the module_mutex Jarkko Sakkinen
2020-07-24 10:22 ` Mike Rapoport
2020-07-25 2:42 ` Jarkko Sakkinen
2020-07-24 14:46 ` Masami Hiramatsu
2020-07-25 2:48 ` Jarkko Sakkinen
2020-07-24 5:05 ` [PATCH v5 2/6] vmalloc: Add text_alloc() and text_free() Jarkko Sakkinen
2020-07-24 10:22 ` Mike Rapoport
2020-07-25 2:20 ` Jarkko Sakkinen
2020-07-24 5:05 ` Jarkko Sakkinen [this message]
2020-07-24 9:22 ` [PATCH v5 3/6] arch/x86: Implement " Ingo Molnar
2020-07-25 2:03 ` Jarkko Sakkinen
2020-07-24 5:05 ` [PATCH v5 4/6] arch/x86: kprobes: Use " Jarkko Sakkinen
2020-07-24 5:05 ` [PATCH v5 5/6] " Jarkko Sakkinen
2020-07-24 9:27 ` Ingo Molnar
2020-07-24 12:16 ` Ard Biesheuvel
2020-07-25 3:19 ` [PATCH v5 5/6] kprobes: Use text_alloc() and text_free()] Jarkko Sakkinen
2020-07-25 3:16 ` [PATCH v5 5/6] kprobes: Use text_alloc() and text_free() Jarkko Sakkinen
2020-07-26 8:14 ` Mike Rapoport
2020-07-26 16:06 ` Ard Biesheuvel
2020-07-28 8:17 ` Masami Hiramatsu
2020-07-28 10:56 ` Ard Biesheuvel
2020-07-28 13:35 ` Masami Hiramatsu
2020-07-28 17:51 ` Ard Biesheuvel
2020-07-29 1:50 ` Masami Hiramatsu
2020-07-29 6:13 ` Ard Biesheuvel
2020-07-30 1:09 ` Masami Hiramatsu
2020-08-18 5:30 ` Jarkko Sakkinen
2020-08-18 11:51 ` Mike Rapoport
2020-08-18 16:30 ` Jarkko Sakkinen
2020-08-19 6:47 ` Mike Rapoport
2020-08-19 21:07 ` Jarkko Sakkinen
2020-07-24 10:27 ` Mike Rapoport
2020-07-24 14:57 ` Masami Hiramatsu
2020-07-24 23:38 ` Jarkko Sakkinen
2020-07-24 5:05 ` [PATCH v5 6/6] kprobes: Remove CONFIG_MODULES dependency Jarkko Sakkinen
2020-07-24 7:01 ` [PATCH v5 0/6] arch/x86: kprobes: Remove MODULES dependency Jarkko Sakkinen
2020-07-24 10:26 ` Mike Rapoport
-- strict thread matches above, loose matches on Subject: below --
2020-07-24 5:04 Jarkko Sakkinen
2020-07-24 5:04 ` [PATCH v5 3/6] arch/x86: Implement text_alloc() and text_free() Jarkko Sakkinen
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