Merge tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull modules updates from Luis Chamberlain:
"Summary of the changes worth highlighting from most interesting to
boring below:

- Christoph Hellwig's symbol_get() fix to Nvidia's efforts to
circumvent the protection he put in place in year 2020 to prevent
proprietary modules from using GPL only symbols, and also ensuring
proprietary modules which export symbols grandfather their taint.

That was done through year 2020 commit 262e6ae7081d ("modules:
inherit TAINT_PROPRIETARY_MODULE"). Christoph's new fix is done by
clarifing __symbol_get() was only ever intended to prevent module
reference loops by Linux kernel modules and so making it only find
symbols exported via EXPORT_SYMBOL_GPL(). The circumvention tactic
used by Nvidia was to use symbol_get() to purposely swift through
proprietary module symbols and completely bypass our traditional
EXPORT_SYMBOL*() annotations and community agreed upon
restrictions.

A small set of preamble patches fix up a few symbols which just
needed adjusting for this on two modules, the rtc ds1685 and the
networking enetc module. Two other modules just needed some build
fixing and removal of use of __symbol_get() as they can't ever be
modular, as was done by Arnd on the ARM pxa module and Christoph
did on the mmc au1xmmc driver.

This is a good reminder to us that symbol_get() is just a hack to
address things which should be fixed through Kconfig at build time
as was done in the later patches, and so ultimately it should just
go.

- Extremely late minor fix for old module layout 055f23b74b20
("module: check for exit sections in layout_sections() instead of
module_init_section()") by James Morse for arm64. Note that this
layout thing is old, it is *not* Song Liu's commit ac3b43283923
("module: replace module_layout with module_memory"). The issue
however is very odd to run into and so there was no hurry to get
this in fast.

- Although the fix did not go through the modules tree I'd like to
highlight the fix by Peter Zijlstra in commit 54097309620e
("x86/static_call: Fix __static_call_fixup()") now merged in your
tree which came out of what was originally suspected to be a
fallout of the the newer module layout changes by Song Liu commit
ac3b43283923 ("module: replace module_layout with module_memory")
instead of module_init_section()"). Thanks to the report by
Christian Bricart and the debugging by Song Liu & Peter that turned
to be noted as a kernel regression in place since v5.19 through
commit ee88d363d156 ("x86,static_call: Use alternative RET
encoding").

I highlight this to reflect and clarify that we haven't seen more
fallout from ac3b43283923 ("module: replace module_layout with
module_memory").

- RISC-V toolchain got mapping symbol support which prefix symbols
with "$" to help with alignment considerations for disassembly.

This is used to differentiate between incompatible instruction
encodings when disassembling. RISC-V just matches what ARM/AARCH64
did for alignment considerations and Palmer Dabbelt extended
is_mapping_symbol() to accept these symbols for RISC-V. We already
had support for this for all architectures but it also checked for
the second character, the RISC-V check Dabbelt added was just for
the "$". After a bit of testing and fallout on linux-next and based
on feedback from Masahiro Yamada it was decided to simplify the
check and treat the first char "$" as unique for all architectures,
and so we no make is_mapping_symbol() for all archs if the symbol
starts with "$".

The most relevant commit for this for RISC-V on binutils was:

https://sourceware.org/pipermail/binutils/2021-July/117350.html

- A late fix by Andrea Righi (today) to make module zstd
decompression use vmalloc() instead of kmalloc() to account for
large compressed modules. I suspect we'll see similar things for
other decompression algorithms soon.

- samples/hw_breakpoint minor fixes by Rong Tao, Arnd Bergmann and
Chen Jiahao"

* tag 'modules-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
module/decompress: use vmalloc() for zstd decompression workspace
kallsyms: Add more debug output for selftest
ARM: module: Use module_init_layout_section() to spot init sections
arm64: module: Use module_init_layout_section() to spot init sections
module: Expose module_init_layout_section()
modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules
rtc: ds1685: use EXPORT_SYMBOL_GPL for ds1685_rtc_poweroff
net: enetc: use EXPORT_SYMBOL_GPL for enetc_phc_index
mmc: au1xmmc: force non-modular build and remove symbol_get usage
ARM: pxa: remove use of symbol_get()
samples/hw_breakpoint: mark sample_hbp as static
samples/hw_breakpoint: fix building without module unloading
samples/hw_breakpoint: Fix kernel BUG 'invalid opcode: 0000'
modpost, kallsyms: Treat add '$'-prefixed symbols as mapping symbols
kernel: params: Remove unnecessary ‘0’ values from err
module: Ignore RISC-V mapping symbols too

arch/arm/kernel/module-plts.c

···
 		/* sort by type and symbol index */
 		sort(rels, numrels, sizeof(Elf32_Rel), cmp_rel, NULL);
 
-		if (strncmp(secstrings + dstsec->sh_name, ".init", 5) != 0)
+		if (!module_init_layout_section(secstrings + dstsec->sh_name))
 			core_plts += count_plts(syms, dstsec->sh_addr, rels,
 						numrels, s->sh_info);
 		else

arch/arm/mach-pxa/sharpsl_pm.c

···
 {
 	schedule_delayed_work(&sharpsl_bat, msecs_to_jiffies(125));
 }
-EXPORT_SYMBOL(sharpsl_battery_kick);
-
 
 static void sharpsl_battery_thread(struct work_struct *private_)
 {

arch/arm/mach-pxa/spitz.c

···
  */
 
 #include <linux/kernel.h>
-#include <linux/module.h>	/* symbol_get ; symbol_put */
 #include <linux/platform_device.h>
 #include <linux/delay.h>
 #include <linux/gpio_keys.h>
···
 	},
 };
 
-static void spitz_bl_kick_battery(void)
-{
-	void (*kick_batt)(void);
-
-	kick_batt = symbol_get(sharpsl_battery_kick);
-	if (kick_batt) {
-		kick_batt();
-		symbol_put(sharpsl_battery_kick);
-	}
-}
-
 static struct gpiod_lookup_table spitz_lcdcon_gpio_table = {
 	.dev_id = "spi2.1",
 	.table = {
···
 	.max_intensity		= 0x2f,
 	.default_intensity	= 0x1f,
 	.limit_mask		= 0x0b,
-	.kick_battery		= spitz_bl_kick_battery,
+	.kick_battery		= sharpsl_battery_kick,
 };
 
 static struct spi_board_info spitz_spi_devices[] = {

arch/arm64/kernel/module-plts.c

···
 		if (nents)
 			sort(rels, nents, sizeof(Elf64_Rela), cmp_rela, NULL);
 
-		if (!str_has_prefix(secstrings + dstsec->sh_name, ".init"))
+		if (!module_init_layout_section(secstrings + dstsec->sh_name))
 			core_plts += count_plts(syms, rels, numrels,
 						sechdrs[i].sh_info, dstsec);
 		else

arch/mips/alchemy/devboards/db1000.c

···
 #include <linux/interrupt.h>
 #include <linux/leds.h>
 #include <linux/mmc/host.h>
-#include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/spi/spi.h>
···
 
 static irqreturn_t db1100_mmc_cd(int irq, void *ptr)
 {
-	void (*mmc_cd)(struct mmc_host *, unsigned long);
-	/* link against CONFIG_MMC=m */
-	mmc_cd = symbol_get(mmc_detect_change);
-	mmc_cd(ptr, msecs_to_jiffies(500));
-	symbol_put(mmc_detect_change);
-
+	mmc_detect_change(ptr, msecs_to_jiffies(500));
 	return IRQ_HANDLED;
 }
 

arch/mips/alchemy/devboards/db1200.c

···
 #include <linux/gpio.h>
 #include <linux/i2c.h>
 #include <linux/init.h>
-#include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/leds.h>
···
 
 static irqreturn_t db1200_mmc_cdfn(int irq, void *ptr)
 {
-	void (*mmc_cd)(struct mmc_host *, unsigned long);
-
-	/* link against CONFIG_MMC=m */
-	mmc_cd = symbol_get(mmc_detect_change);
-	if (mmc_cd) {
-		mmc_cd(ptr, msecs_to_jiffies(200));
-		symbol_put(mmc_detect_change);
-	}
+	mmc_detect_change(ptr, msecs_to_jiffies(200));
 
 	msleep(100);	/* debounce */
 	if (irq == DB1200_SD0_INSERT_INT)
···
 
 static irqreturn_t pb1200_mmc1_cdfn(int irq, void *ptr)
 {
-	void (*mmc_cd)(struct mmc_host *, unsigned long);
-
-	/* link against CONFIG_MMC=m */
-	mmc_cd = symbol_get(mmc_detect_change);
-	if (mmc_cd) {
-		mmc_cd(ptr, msecs_to_jiffies(200));
-		symbol_put(mmc_detect_change);
-	}
+	mmc_detect_change(ptr, msecs_to_jiffies(200));
 
 	msleep(100);	/* debounce */
 	if (irq == PB1200_SD1_INSERT_INT)

arch/mips/alchemy/devboards/db1300.c

···
 #include <linux/interrupt.h>
 #include <linux/ata_platform.h>
 #include <linux/mmc/host.h>
-#include <linux/module.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/platnand.h>
 #include <linux/platform_device.h>
···
 
 static irqreturn_t db1300_mmc_cdfn(int irq, void *ptr)
 {
-	void (*mmc_cd)(struct mmc_host *, unsigned long);
-
-	/* link against CONFIG_MMC=m.  We can only be called once MMC core has
-	 * initialized the controller, so symbol_get() should always succeed.
-	 */
-	mmc_cd = symbol_get(mmc_detect_change);
-	mmc_cd(ptr, msecs_to_jiffies(200));
-	symbol_put(mmc_detect_change);
+	mmc_detect_change(ptr, msecs_to_jiffies(200));
 
 	msleep(100);	/* debounce */
 	if (irq == DB1300_SD1_INSERT_INT)

drivers/mmc/host/Kconfig

···
 	  of Alcor Micro PCI-E card reader
 
 config MMC_AU1X
-	tristate "Alchemy AU1XX0 MMC Card Interface support"
+	bool "Alchemy AU1XX0 MMC Card Interface support"
 	depends on MIPS_ALCHEMY
+	depends on MMC=y
 	help
 	  This selects the AMD Alchemy(R) Multimedia card interface.
-	  If you have a Alchemy platform with a MMC slot, say Y or M here.
+	  If you have a Alchemy platform with a MMC slot, say Y here.
 
 	  If unsure, say N.
 

drivers/net/ethernet/freescale/enetc/enetc_ptp.c

···
 #include "enetc.h"
 
 int enetc_phc_index = -1;
-EXPORT_SYMBOL(enetc_phc_index);
+EXPORT_SYMBOL_GPL(enetc_phc_index);
 
 static struct ptp_clock_info enetc_ptp_caps = {
 	.owner		= THIS_MODULE,

drivers/rtc/rtc-ds1685.c

···
 		unreachable();
 	}
 }
-EXPORT_SYMBOL(ds1685_rtc_poweroff);
+EXPORT_SYMBOL_GPL(ds1685_rtc_poweroff);
 /* ----------------------------------------------------------------------- */
 
 

include/linux/module_symbol.h

···
 		return true;
 	if (str[0] == 'L' && str[1] == '0')
 		return true;
-	return str[0] == '$' &&
-	       (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
-	       && (str[2] == '\0' || str[2] == '.');
+	return str[0] == '$';
 }
 
 #endif /* _LINUX_MODULE_SYMBOL_H */

include/linux/moduleloader.h

···
  */
 bool module_exit_section(const char *name);
 
+/* Describes whether within_module_init() will consider this an init section
+ * or not. This behaviour changes with CONFIG_MODULE_UNLOAD.
+ */
+bool module_init_layout_section(const char *sname);
+
 /*
  * Apply the given relocation to the (simplified) ELF.  Return -error
  * or 0.

kernel/kallsyms_selftest.c

···
 		ret = lookup_symbol_name(addr, namebuf);
 		if (unlikely(ret)) {
 			namebuf[0] = 0;
+			pr_info("%d: lookup_symbol_name(%lx) failed\n", i, addr);
 			goto failed;
 		}
 
···
 			if (stat->addr != stat2->addr ||
 			    stat->real_cnt != stat2->real_cnt ||
 			    memcmp(stat->addrs, stat2->addrs,
-				   stat->save_cnt * sizeof(stat->addrs[0])))
+				   stat->save_cnt * sizeof(stat->addrs[0]))) {
+				pr_info("%s: mismatch between kallsyms_on_each_symbol() and kallsyms_on_each_match_symbol()\n",
+					namebuf);
 				goto failed;
+			}
 
 			/*
 			 * The average of random increments is 128, that is, one of
···
 		}
 
 		/* Need to be found at least once */
-		if (!stat->real_cnt)
+		if (!stat->real_cnt) {
+			pr_info("%s: Never found\n", namebuf);
 			goto failed;
+		}
 
 		/*
 		 * kallsyms_lookup_name() returns the address of the first
 		 * symbol found and cannot be NULL.
 		 */
-		if (!lookup_addr || lookup_addr != stat->addrs[0])
+		if (!lookup_addr) {
+			pr_info("%s: NULL lookup_addr?!\n", namebuf);
 			goto failed;
+		}
+		if (lookup_addr != stat->addrs[0]) {
+			pr_info("%s: lookup_addr != stat->addrs[0]\n", namebuf);
+			goto failed;
+		}
 
 		/*
 		 * If the addresses of all matching symbols are recorded, the
···
 					break;
 			}
 
-			if (j == stat->save_cnt)
+			if (j == stat->save_cnt) {
+				pr_info("%s: j == save_cnt?!\n", namebuf);
 				goto failed;
+			}
 		}
 	}
 

kernel/module/decompress.c

···
 	}
 
 	wksp_size = zstd_dstream_workspace_bound(header.windowSize);
-	wksp = kmalloc(wksp_size, GFP_KERNEL);
+	wksp = vmalloc(wksp_size);
 	if (!wksp) {
 		retval = -ENOMEM;
 		goto out;
···
 	retval = new_size;
 
  out:
-	kfree(wksp);
+	vfree(wksp);
 	return retval;
 }
 #else

kernel/module/main.c

···
 	};
 
 	preempt_disable();
-	if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) {
-		preempt_enable();
-		return NULL;
+	if (!find_symbol(&fsa))
+		goto fail;
+	if (fsa.license != GPL_ONLY) {
+		pr_warn("failing symbol_get of non-GPLONLY symbol %s.\n",
+			symbol);
+		goto fail;
 	}
+	if (strong_try_module_get(fsa.owner))
+		goto fail;
 	preempt_enable();
 	return (void *)kernel_symbol_value(fsa.sym);
+fail:
+	preempt_enable();
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(__symbol_get);
 
···
 	return offset | mask;
 }
 
-static bool module_init_layout_section(const char *sname)
+bool module_init_layout_section(const char *sname)
 {
 #ifndef CONFIG_MODULE_UNLOAD
 	if (module_exit_section(sname))

kernel/params.c

···
 
 int param_set_bool_enable_only(const char *val, const struct kernel_param *kp)
 {
-	int err = 0;
+	int err;
 	bool new_value;
 	bool orig_value = *(bool *)kp->arg;
 	struct kernel_param dummy_kp = *kp;

samples/hw_breakpoint/data_breakpoint.c

···
 #include <linux/perf_event.h>
 #include <linux/hw_breakpoint.h>
 
-struct perf_event * __percpu *sample_hbp;
+static struct perf_event * __percpu *sample_hbp;
 
 static char ksym_name[KSYM_NAME_LEN] = "jiffies";
 module_param_string(ksym, ksym_name, KSYM_NAME_LEN, S_IRUGO);
···
 static void __exit hw_break_module_exit(void)
 {
 	unregister_wide_hw_breakpoint(sample_hbp);
-	symbol_put(ksym_name);
+#ifdef CONFIG_MODULE_UNLOAD
+	__symbol_put(ksym_name);
+#endif
 	printk(KERN_INFO "HW Breakpoint for %s write uninstalled\n", ksym_name);
 }