* Re: [PATCH v12 01/14] ARM: mm: add missing pud_page define to 2-level page tables
From: Ding Tianhong @ 2021-02-02 11:48 UTC (permalink / raw)
To: Russell King - ARM Linux admin, Nicholas Piggin
Cc: linux-arch, linux-kernel, Christoph Hellwig, linux-mm,
Jonathan Cameron, Andrew Morton, Rick Edgecombe, linuxppc-dev,
linux-arm-kernel
In-Reply-To: <d1f661f2-f473-1dd8-94cc-fe76714249b5@huawei.com>
On 2021/2/2 19:47, Ding Tianhong wrote:
> On 2021/2/2 19:13, Russell King - ARM Linux admin wrote:
>> On Tue, Feb 02, 2021 at 09:05:02PM +1000, Nicholas Piggin wrote:
>>> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
>>> index c02f24400369..d63a5bb6bd0c 100644
>>> --- a/arch/arm/include/asm/pgtable.h
>>> +++ b/arch/arm/include/asm/pgtable.h
>>> @@ -166,6 +166,9 @@ extern struct page *empty_zero_page;
>>>
>>> extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
>>>
>>> +#define pud_page(pud) pmd_page(__pmd(pud_val(pud)))
>>> +#define pud_write(pud) pmd_write(__pmd(pud_val(pud)))
>>
>> As there is no PUD, does it really make sense to return a valid
>> struct page (which will be the PTE page) for pud_page(), which is
>> several tables above?
>>
> --- a/arch/arm/include/asm/pgtable-2level.h
> +++ b/arch/arm/include/asm/pgtable-2level.h
>
> +static inline int pud_none(pud_t pud)
> +{
> + return 0;
> +}
>
--- a/arch/arm/include/asm/pgtable-2level.h
+++ b/arch/arm/include/asm/pgtable-2level.h>
+static inline int pud_page(pud_t pud)
+{
+ return 0;
+}
> I think it could be fix like this.
>
> Ding
>
^ permalink raw reply
* Re: [PATCH v12 01/14] ARM: mm: add missing pud_page define to 2-level page tables
From: Russell King - ARM Linux admin @ 2021-02-02 12:07 UTC (permalink / raw)
To: Ding Tianhong
Cc: linux-arch, linux-kernel, Nicholas Piggin, Christoph Hellwig,
linux-mm, Jonathan Cameron, Andrew Morton, Rick Edgecombe,
linuxppc-dev, linux-arm-kernel
In-Reply-To: <d1f661f2-f473-1dd8-94cc-fe76714249b5@huawei.com>
On Tue, Feb 02, 2021 at 07:47:04PM +0800, Ding Tianhong wrote:
> On 2021/2/2 19:13, Russell King - ARM Linux admin wrote:
> > On Tue, Feb 02, 2021 at 09:05:02PM +1000, Nicholas Piggin wrote:
> >> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
> >> index c02f24400369..d63a5bb6bd0c 100644
> >> --- a/arch/arm/include/asm/pgtable.h
> >> +++ b/arch/arm/include/asm/pgtable.h
> >> @@ -166,6 +166,9 @@ extern struct page *empty_zero_page;
> >>
> >> extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
> >>
> >> +#define pud_page(pud) pmd_page(__pmd(pud_val(pud)))
> >> +#define pud_write(pud) pmd_write(__pmd(pud_val(pud)))
> >
> > As there is no PUD, does it really make sense to return a valid
> > struct page (which will be the PTE page) for pud_page(), which is
> > several tables above?
> >
> --- a/arch/arm/include/asm/pgtable-2level.h
> +++ b/arch/arm/include/asm/pgtable-2level.h
>
> +static inline int pud_none(pud_t pud)
> +{
> + return 0;
> +}
>
> I think it could be fix like this.
We already have that.
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
^ permalink raw reply
* [PATCH 03/13] module: unexport find_module and module_mutex
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
find_module is not used by modular code any more, and random driver code
has no business calling it to start with.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
---
kernel/module.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index 4bf30e4b3eaaa1..981302f616b411 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -88,7 +88,6 @@
* (delete and add uses RCU list operations).
*/
DEFINE_MUTEX(module_mutex);
-EXPORT_SYMBOL_GPL(module_mutex);
static LIST_HEAD(modules);
/* Work queue for freeing init sections in success case */
@@ -672,7 +671,6 @@ struct module *find_module(const char *name)
module_assert_mutex();
return find_module_all(name, strlen(name), false);
}
-EXPORT_SYMBOL_GPL(find_module);
#ifdef CONFIG_SMP
--
2.29.2
^ permalink raw reply related
* module loader dead code removal and cleanups v3
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
Hi all,
this series removes support for long term unused export types and
cleans up various loose ends in the module loader.
Changes since v2:
- clean up klp_find_object_symbol a bit
- remove the now unused module_assert_mutex helper
Changes since v1:
- move struct symsearch to module.c
- rework drm to not call find_module at all
- allow RCU-sched locking for find_module
- keep find_module as a public API instead of module_loaded
- update a few comments and commit logs
Diffstat:
^ permalink raw reply
* [PATCH 02/13] drm: remove drm_fb_helper_modinit
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
drm_fb_helper_modinit has a lot of boilerplate for what is not very
simple functionality. Just open code it in the only caller using
IS_ENABLED and IS_MODULE, and skip the find_module check as a
request_module is harmless if the module is already loaded (and not
other caller has this find_module check either).
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/gpu/drm/drm_crtc_helper_internal.h | 10 ---------
drivers/gpu/drm/drm_fb_helper.c | 21 ------------------
drivers/gpu/drm/drm_kms_helper_common.c | 25 +++++++++++-----------
3 files changed, 12 insertions(+), 44 deletions(-)
diff --git a/drivers/gpu/drm/drm_crtc_helper_internal.h b/drivers/gpu/drm/drm_crtc_helper_internal.h
index 25ce42e799952c..61e09f8a8d0ff0 100644
--- a/drivers/gpu/drm/drm_crtc_helper_internal.h
+++ b/drivers/gpu/drm/drm_crtc_helper_internal.h
@@ -32,16 +32,6 @@
#include <drm/drm_encoder.h>
#include <drm/drm_modes.h>
-/* drm_fb_helper.c */
-#ifdef CONFIG_DRM_FBDEV_EMULATION
-int drm_fb_helper_modinit(void);
-#else
-static inline int drm_fb_helper_modinit(void)
-{
- return 0;
-}
-#endif
-
/* drm_dp_aux_dev.c */
#ifdef CONFIG_DRM_DP_AUX_CHARDEV
int drm_dp_aux_dev_init(void);
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 4b81195106875d..0b9f1ae1b7864c 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -2499,24 +2499,3 @@ void drm_fbdev_generic_setup(struct drm_device *dev,
drm_client_register(&fb_helper->client);
}
EXPORT_SYMBOL(drm_fbdev_generic_setup);
-
-/* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
- * but the module doesn't depend on any fb console symbols. At least
- * attempt to load fbcon to avoid leaving the system without a usable console.
- */
-int __init drm_fb_helper_modinit(void)
-{
-#if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
- const char name[] = "fbcon";
- struct module *fbcon;
-
- mutex_lock(&module_mutex);
- fbcon = find_module(name);
- mutex_unlock(&module_mutex);
-
- if (!fbcon)
- request_module_nowait(name);
-#endif
- return 0;
-}
-EXPORT_SYMBOL(drm_fb_helper_modinit);
diff --git a/drivers/gpu/drm/drm_kms_helper_common.c b/drivers/gpu/drm/drm_kms_helper_common.c
index 221a8528c9937a..f933da1656eb52 100644
--- a/drivers/gpu/drm/drm_kms_helper_common.c
+++ b/drivers/gpu/drm/drm_kms_helper_common.c
@@ -64,19 +64,18 @@ MODULE_PARM_DESC(edid_firmware,
static int __init drm_kms_helper_init(void)
{
- int ret;
-
- /* Call init functions from specific kms helpers here */
- ret = drm_fb_helper_modinit();
- if (ret < 0)
- goto out;
-
- ret = drm_dp_aux_dev_init();
- if (ret < 0)
- goto out;
-
-out:
- return ret;
+ /*
+ * The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
+ * but the module doesn't depend on any fb console symbols. At least
+ * attempt to load fbcon to avoid leaving the system without a usable
+ * console.
+ */
+ if (IS_ENABLED(CONFIG_DRM_FBDEV_EMULATION) &&
+ IS_MODULE(CONFIG_FRAMEBUFFER_CONSOLE) &&
+ !IS_ENABLED(CONFIG_EXPERT))
+ request_module_nowait("fbcon");
+
+ return drm_dp_aux_dev_init();
}
static void __exit drm_kms_helper_exit(void)
--
2.29.2
^ permalink raw reply related
* [PATCH 01/13] powerpc/powernv: remove get_cxl_module
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
The static inline get_cxl_module function is entirely unused since commit
8bf6b91a5125a ("Revert "powerpc/powernv: Add support for the cxl kernel
api on the real phb"), so remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
---
arch/powerpc/platforms/powernv/pci-cxl.c | 22 ----------------------
1 file changed, 22 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-cxl.c b/arch/powerpc/platforms/powernv/pci-cxl.c
index 8c739c94ed28d6..53172862d23bd3 100644
--- a/arch/powerpc/platforms/powernv/pci-cxl.c
+++ b/arch/powerpc/platforms/powernv/pci-cxl.c
@@ -150,25 +150,3 @@ int pnv_cxl_ioda_msi_setup(struct pci_dev *dev, unsigned int hwirq,
return 0;
}
EXPORT_SYMBOL(pnv_cxl_ioda_msi_setup);
-
-#if IS_MODULE(CONFIG_CXL)
-static inline int get_cxl_module(void)
-{
- struct module *cxl_module;
-
- mutex_lock(&module_mutex);
-
- cxl_module = find_module("cxl");
- if (cxl_module)
- __module_get(cxl_module);
-
- mutex_unlock(&module_mutex);
-
- if (!cxl_module)
- return -ENODEV;
-
- return 0;
-}
-#else
-static inline int get_cxl_module(void) { return 0; }
-#endif
--
2.29.2
^ permalink raw reply related
* [PATCH 04/13] module: use RCU to synchronize find_module
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
Allow for a RCU-sched critical section around find_module, following
the lower level find_module_all helper, and switch the two callers
outside of module.c to use such a RCU-sched critical section instead
of module_mutex.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
---
include/linux/module.h | 2 +-
kernel/livepatch/core.c | 5 +++--
kernel/module.c | 1 -
kernel/trace/trace_kprobe.c | 4 ++--
4 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/include/linux/module.h b/include/linux/module.h
index 7a0bcb5b1ffccd..a64aa84d1b182c 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -586,7 +586,7 @@ static inline bool within_module(unsigned long addr, const struct module *mod)
return within_module_init(addr, mod) || within_module_core(addr, mod);
}
-/* Search for module by name: must hold module_mutex. */
+/* Search for module by name: must be in a RCU-sched critical section. */
struct module *find_module(const char *name);
struct symsearch {
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index f76fdb9255323d..262cd9b003b9f0 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -19,6 +19,7 @@
#include <linux/moduleloader.h>
#include <linux/completion.h>
#include <linux/memory.h>
+#include <linux/rcupdate.h>
#include <asm/cacheflush.h>
#include "core.h"
#include "patch.h"
@@ -57,7 +58,7 @@ static void klp_find_object_module(struct klp_object *obj)
if (!klp_is_module(obj))
return;
- mutex_lock(&module_mutex);
+ rcu_read_lock_sched();
/*
* We do not want to block removal of patched modules and therefore
* we do not take a reference here. The patches are removed by
@@ -74,7 +75,7 @@ static void klp_find_object_module(struct klp_object *obj)
if (mod && mod->klp_alive)
obj->mod = mod;
- mutex_unlock(&module_mutex);
+ rcu_read_unlock_sched();
}
static bool klp_initialized(void)
diff --git a/kernel/module.c b/kernel/module.c
index 981302f616b411..6772fb2680eb3e 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -668,7 +668,6 @@ static struct module *find_module_all(const char *name, size_t len,
struct module *find_module(const char *name)
{
- module_assert_mutex();
return find_module_all(name, strlen(name), false);
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index e6fba1798771b4..3137992baa5e7a 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -124,9 +124,9 @@ static nokprobe_inline bool trace_kprobe_module_exist(struct trace_kprobe *tk)
if (!p)
return true;
*p = '\0';
- mutex_lock(&module_mutex);
+ rcu_read_lock_sched();
ret = !!find_module(tk->symbol);
- mutex_unlock(&module_mutex);
+ rcu_read_unlock_sched();
*p = ':';
return ret;
--
2.29.2
^ permalink raw reply related
* [PATCH 05/13] kallsyms: refactor {,module_}kallsyms_on_each_symbol
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
Require an explicit call to module_kallsyms_on_each_symbol to look
for symbols in modules instead of the call from kallsyms_on_each_symbol,
and acquire module_mutex inside of module_kallsyms_on_each_symbol instead
of leaving that up to the caller. Note that this slightly changes the
behavior for the livepatch code in that the symbols from vmlinux are not
iterated anymore if objname is set, but that actually is the desired
behavior in this case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Miroslav Benes <mbenes@suse.cz>
---
kernel/kallsyms.c | 6 +++++-
kernel/livepatch/core.c | 2 --
kernel/module.c | 13 ++++---------
3 files changed, 9 insertions(+), 12 deletions(-)
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index fe9de067771c34..a0d3f0865916f9 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -177,6 +177,10 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}
+/*
+ * Iterate over all symbols in vmlinux. For symbols from modules use
+ * module_kallsyms_on_each_symbol instead.
+ */
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data)
@@ -192,7 +196,7 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
if (ret != 0)
return ret;
}
- return module_kallsyms_on_each_symbol(fn, data);
+ return 0;
}
static unsigned long get_symbol_pos(unsigned long addr,
diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index 262cd9b003b9f0..335d988bd81117 100644
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -164,12 +164,10 @@ static int klp_find_object_symbol(const char *objname, const char *name,
.pos = sympos,
};
- mutex_lock(&module_mutex);
if (objname)
module_kallsyms_on_each_symbol(klp_find_callback, &args);
else
kallsyms_on_each_symbol(klp_find_callback, &args);
- mutex_unlock(&module_mutex);
/*
* Ensure an address was found. If sympos is 0, ensure symbol is unique;
diff --git a/kernel/module.c b/kernel/module.c
index 6772fb2680eb3e..25345792c770d1 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -255,11 +255,6 @@ static void mod_update_bounds(struct module *mod)
struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
#endif /* CONFIG_KGDB_KDB */
-static void module_assert_mutex(void)
-{
- lockdep_assert_held(&module_mutex);
-}
-
static void module_assert_mutex_or_preempt(void)
{
#ifdef CONFIG_LOCKDEP
@@ -4379,8 +4374,7 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
unsigned int i;
int ret;
- module_assert_mutex();
-
+ mutex_lock(&module_mutex);
list_for_each_entry(mod, &modules, list) {
/* We hold module_mutex: no need for rcu_dereference_sched */
struct mod_kallsyms *kallsyms = mod->kallsyms;
@@ -4396,10 +4390,11 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
ret = fn(data, kallsyms_symbol_name(kallsyms, i),
mod, kallsyms_symbol_value(sym));
if (ret != 0)
- return ret;
+ break;
}
}
- return 0;
+ mutex_unlock(&module_mutex);
+ return ret;
}
#endif /* CONFIG_KALLSYMS */
--
2.29.2
^ permalink raw reply related
* [PATCH 06/13] kallsyms: only build {, module_}kallsyms_on_each_symbol when required
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
kallsyms_on_each_symbol and module_kallsyms_on_each_symbol are only used
by the livepatching code, so don't build them if livepatching is not
enabled.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/kallsyms.h | 17 ++++-------------
include/linux/module.h | 16 ++++------------
kernel/kallsyms.c | 2 ++
kernel/module.c | 2 ++
4 files changed, 12 insertions(+), 25 deletions(-)
diff --git a/include/linux/kallsyms.h b/include/linux/kallsyms.h
index 481273f0c72d42..465060acc9816f 100644
--- a/include/linux/kallsyms.h
+++ b/include/linux/kallsyms.h
@@ -71,15 +71,14 @@ static inline void *dereference_symbol_descriptor(void *ptr)
return ptr;
}
-#ifdef CONFIG_KALLSYMS
-/* Lookup the address for a symbol. Returns 0 if not found. */
-unsigned long kallsyms_lookup_name(const char *name);
-
-/* Call a function on each kallsyms symbol in the core kernel */
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data);
+#ifdef CONFIG_KALLSYMS
+/* Lookup the address for a symbol. Returns 0 if not found. */
+unsigned long kallsyms_lookup_name(const char *name);
+
extern int kallsyms_lookup_size_offset(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset);
@@ -108,14 +107,6 @@ static inline unsigned long kallsyms_lookup_name(const char *name)
return 0;
}
-static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *,
- struct module *,
- unsigned long),
- void *data)
-{
- return 0;
-}
-
static inline int kallsyms_lookup_size_offset(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset)
diff --git a/include/linux/module.h b/include/linux/module.h
index a64aa84d1b182c..3ea4ffae608f97 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -608,10 +608,6 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name);
-int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
- struct module *, unsigned long),
- void *data);
-
extern void __noreturn __module_put_and_exit(struct module *mod,
long code);
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code)
@@ -795,14 +791,6 @@ static inline unsigned long module_kallsyms_lookup_name(const char *name)
return 0;
}
-static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
- struct module *,
- unsigned long),
- void *data)
-{
- return 0;
-}
-
static inline int register_module_notifier(struct notifier_block *nb)
{
/* no events will happen anyway, so this can always succeed */
@@ -891,4 +879,8 @@ static inline bool module_sig_ok(struct module *module)
}
#endif /* CONFIG_MODULE_SIG */
+int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
+ struct module *, unsigned long),
+ void *data);
+
#endif /* _LINUX_MODULE_H */
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index a0d3f0865916f9..8043a90aa50ed3 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -177,6 +177,7 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}
+#ifdef CONFIG_LIVEPATCH
/*
* Iterate over all symbols in vmlinux. For symbols from modules use
* module_kallsyms_on_each_symbol instead.
@@ -198,6 +199,7 @@ int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
}
return 0;
}
+#endif /* CONFIG_LIVEPATCH */
static unsigned long get_symbol_pos(unsigned long addr,
unsigned long *symbolsize,
diff --git a/kernel/module.c b/kernel/module.c
index 25345792c770d1..470fd9d9d68f97 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -4366,6 +4366,7 @@ unsigned long module_kallsyms_lookup_name(const char *name)
return ret;
}
+#ifdef CONFIG_LIVEPATCH
int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *, unsigned long),
void *data)
@@ -4396,6 +4397,7 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
mutex_unlock(&module_mutex);
return ret;
}
+#endif /* CONFIG_LIVEPATCH */
#endif /* CONFIG_KALLSYMS */
/* Maximum number of characters written by module_flags() */
--
2.29.2
^ permalink raw reply related
* [PATCH 07/13] module: mark module_mutex static
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
Except for two lockdep asserts module_mutex is only used in module.c.
Remove the two asserts given that the functions they are in are not
exported and just called from the module code, and mark module_mutex
static.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/module.h | 2 --
kernel/module.c | 2 +-
lib/bug.c | 3 ---
3 files changed, 1 insertion(+), 6 deletions(-)
diff --git a/include/linux/module.h b/include/linux/module.h
index 3ea4ffae608f97..0f360c48fe92a6 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -550,8 +550,6 @@ static inline unsigned long kallsyms_symbol_value(const Elf_Sym *sym)
}
#endif
-extern struct mutex module_mutex;
-
/* FIXME: It'd be nice to isolate modules during init, too, so they
aren't used before they (may) fail. But presently too much code
(IDE & SCSI) require entry into the module during init.*/
diff --git a/kernel/module.c b/kernel/module.c
index 470fd9d9d68f97..1635656d47654a 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -87,7 +87,7 @@
* 3) module_addr_min/module_addr_max.
* (delete and add uses RCU list operations).
*/
-DEFINE_MUTEX(module_mutex);
+static DEFINE_MUTEX(module_mutex);
static LIST_HEAD(modules);
/* Work queue for freeing init sections in success case */
diff --git a/lib/bug.c b/lib/bug.c
index 7103440c0ee1af..8f9d537bfb2a59 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -91,8 +91,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
char *secstrings;
unsigned int i;
- lockdep_assert_held(&module_mutex);
-
mod->bug_table = NULL;
mod->num_bugs = 0;
@@ -118,7 +116,6 @@ void module_bug_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
void module_bug_cleanup(struct module *mod)
{
- lockdep_assert_held(&module_mutex);
list_del_rcu(&mod->bug_list);
}
--
2.29.2
^ permalink raw reply related
* [PATCH 08/13] module: remove each_symbol_in_section
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
each_symbol_in_section just contains a trivial loop over its arguments.
Just open code the loop in the two callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
kernel/module.c | 29 +++++++----------------------
1 file changed, 7 insertions(+), 22 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index 1635656d47654a..b050c836a0061f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -428,30 +428,13 @@ extern const s32 __start___kcrctab_unused_gpl[];
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif
-static bool each_symbol_in_section(const struct symsearch *arr,
- unsigned int arrsize,
- struct module *owner,
- bool (*fn)(const struct symsearch *syms,
- struct module *owner,
- void *data),
- void *data)
-{
- unsigned int j;
-
- for (j = 0; j < arrsize; j++) {
- if (fn(&arr[j], owner, data))
- return true;
- }
-
- return false;
-}
-
/* Returns true as soon as fn returns true, otherwise false. */
static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
struct module *owner,
void *data),
void *data)
{
+ unsigned int i;
struct module *mod;
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
@@ -474,8 +457,9 @@ static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
module_assert_mutex_or_preempt();
- if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
- return true;
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (fn(&arr[i], NULL, data))
+ return true;
list_for_each_entry_rcu(mod, &modules, list,
lockdep_is_held(&module_mutex)) {
@@ -504,8 +488,9 @@ static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
if (mod->state == MODULE_STATE_UNFORMED)
continue;
- if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
- return true;
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (fn(&arr[i], mod, data))
+ return true;
}
return false;
}
--
2.29.2
^ permalink raw reply related
* [PATCH 09/13] module: merge each_symbol_section into find_symbol
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
each_symbol_section is only called by find_symbol, so merge the two
functions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
kernel/module.c | 148 ++++++++++++++++++++++--------------------------
1 file changed, 69 insertions(+), 79 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index b050c836a0061f..ab219a16f35068 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -428,73 +428,6 @@ extern const s32 __start___kcrctab_unused_gpl[];
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif
-/* Returns true as soon as fn returns true, otherwise false. */
-static bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
- struct module *owner,
- void *data),
- void *data)
-{
- unsigned int i;
- struct module *mod;
- static const struct symsearch arr[] = {
- { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
- NOT_GPL_ONLY, false },
- { __start___ksymtab_gpl, __stop___ksymtab_gpl,
- __start___kcrctab_gpl,
- GPL_ONLY, false },
- { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
- __start___kcrctab_gpl_future,
- WILL_BE_GPL_ONLY, false },
-#ifdef CONFIG_UNUSED_SYMBOLS
- { __start___ksymtab_unused, __stop___ksymtab_unused,
- __start___kcrctab_unused,
- NOT_GPL_ONLY, true },
- { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
- __start___kcrctab_unused_gpl,
- GPL_ONLY, true },
-#endif
- };
-
- module_assert_mutex_or_preempt();
-
- for (i = 0; i < ARRAY_SIZE(arr); i++)
- if (fn(&arr[i], NULL, data))
- return true;
-
- list_for_each_entry_rcu(mod, &modules, list,
- lockdep_is_held(&module_mutex)) {
- struct symsearch arr[] = {
- { mod->syms, mod->syms + mod->num_syms, mod->crcs,
- NOT_GPL_ONLY, false },
- { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
- mod->gpl_crcs,
- GPL_ONLY, false },
- { mod->gpl_future_syms,
- mod->gpl_future_syms + mod->num_gpl_future_syms,
- mod->gpl_future_crcs,
- WILL_BE_GPL_ONLY, false },
-#ifdef CONFIG_UNUSED_SYMBOLS
- { mod->unused_syms,
- mod->unused_syms + mod->num_unused_syms,
- mod->unused_crcs,
- NOT_GPL_ONLY, true },
- { mod->unused_gpl_syms,
- mod->unused_gpl_syms + mod->num_unused_gpl_syms,
- mod->unused_gpl_crcs,
- GPL_ONLY, true },
-#endif
- };
-
- if (mod->state == MODULE_STATE_UNFORMED)
- continue;
-
- for (i = 0; i < ARRAY_SIZE(arr); i++)
- if (fn(&arr[i], mod, data))
- return true;
- }
- return false;
-}
-
struct find_symbol_arg {
/* Input */
const char *name;
@@ -605,24 +538,81 @@ static const struct kernel_symbol *find_symbol(const char *name,
bool gplok,
bool warn)
{
- struct find_symbol_arg fsa;
+ static const struct symsearch arr[] = {
+ { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
+ NOT_GPL_ONLY, false },
+ { __start___ksymtab_gpl, __stop___ksymtab_gpl,
+ __start___kcrctab_gpl,
+ GPL_ONLY, false },
+ { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
+ __start___kcrctab_gpl_future,
+ WILL_BE_GPL_ONLY, false },
+#ifdef CONFIG_UNUSED_SYMBOLS
+ { __start___ksymtab_unused, __stop___ksymtab_unused,
+ __start___kcrctab_unused,
+ NOT_GPL_ONLY, true },
+ { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
+ __start___kcrctab_unused_gpl,
+ GPL_ONLY, true },
+#endif
+ };
+ struct find_symbol_arg fsa = {
+ .name = name,
+ .gplok = gplok,
+ .warn = warn,
+ };
+ struct module *mod;
+ unsigned int i;
+
+ module_assert_mutex_or_preempt();
+
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (find_exported_symbol_in_section(&arr[i], NULL, &fsa))
+ goto found;
- fsa.name = name;
- fsa.gplok = gplok;
- fsa.warn = warn;
+ list_for_each_entry_rcu(mod, &modules, list,
+ lockdep_is_held(&module_mutex)) {
+ struct symsearch arr[] = {
+ { mod->syms, mod->syms + mod->num_syms, mod->crcs,
+ NOT_GPL_ONLY, false },
+ { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
+ mod->gpl_crcs,
+ GPL_ONLY, false },
+ { mod->gpl_future_syms,
+ mod->gpl_future_syms + mod->num_gpl_future_syms,
+ mod->gpl_future_crcs,
+ WILL_BE_GPL_ONLY, false },
+#ifdef CONFIG_UNUSED_SYMBOLS
+ { mod->unused_syms,
+ mod->unused_syms + mod->num_unused_syms,
+ mod->unused_crcs,
+ NOT_GPL_ONLY, true },
+ { mod->unused_gpl_syms,
+ mod->unused_gpl_syms + mod->num_unused_gpl_syms,
+ mod->unused_gpl_crcs,
+ GPL_ONLY, true },
+#endif
+ };
- if (each_symbol_section(find_exported_symbol_in_section, &fsa)) {
- if (owner)
- *owner = fsa.owner;
- if (crc)
- *crc = fsa.crc;
- if (license)
- *license = fsa.license;
- return fsa.sym;
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (find_exported_symbol_in_section(&arr[i], mod, &fsa))
+ goto found;
}
pr_debug("Failed to find symbol %s\n", name);
return NULL;
+
+found:
+ if (owner)
+ *owner = fsa.owner;
+ if (crc)
+ *crc = fsa.crc;
+ if (license)
+ *license = fsa.license;
+ return fsa.sym;
}
/*
--
2.29.2
^ permalink raw reply related
* [PATCH 11/13] module: move struct symsearch to module.c
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
struct symsearch is only used inside of module.h, so move the definition
out of module.h.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
include/linux/module.h | 11 -----------
kernel/module.c | 11 +++++++++++
2 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/include/linux/module.h b/include/linux/module.h
index 0f360c48fe92a6..da0f5966ee80c9 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -587,17 +587,6 @@ static inline bool within_module(unsigned long addr, const struct module *mod)
/* Search for module by name: must be in a RCU-sched critical section. */
struct module *find_module(const char *name);
-struct symsearch {
- const struct kernel_symbol *start, *stop;
- const s32 *crcs;
- enum mod_license {
- NOT_GPL_ONLY,
- GPL_ONLY,
- WILL_BE_GPL_ONLY,
- } license;
- bool unused;
-};
-
/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
symnum out of range. */
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
diff --git a/kernel/module.c b/kernel/module.c
index 02d1dd9bfc0a90..7a4bce8507b96f 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -428,6 +428,17 @@ extern const s32 __start___kcrctab_unused_gpl[];
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif
+struct symsearch {
+ const struct kernel_symbol *start, *stop;
+ const s32 *crcs;
+ enum mod_license {
+ NOT_GPL_ONLY,
+ GPL_ONLY,
+ WILL_BE_GPL_ONLY,
+ } license;
+ bool unused;
+};
+
struct find_symbol_arg {
/* Input */
const char *name;
--
2.29.2
^ permalink raw reply related
* [PATCH 10/13] module: pass struct find_symbol_args to find_symbol
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
Simplify the calling convention by passing the find_symbol_args structure
to find_symbol instead of initializing it inside the function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
kernel/module.c | 113 ++++++++++++++++++++++--------------------------
1 file changed, 52 insertions(+), 61 deletions(-)
diff --git a/kernel/module.c b/kernel/module.c
index ab219a16f35068..02d1dd9bfc0a90 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -531,12 +531,7 @@ static bool find_exported_symbol_in_section(const struct symsearch *syms,
* Find an exported symbol and return it, along with, (optional) crc and
* (optional) module which owns it. Needs preempt disabled or module_mutex.
*/
-static const struct kernel_symbol *find_symbol(const char *name,
- struct module **owner,
- const s32 **crc,
- enum mod_license *license,
- bool gplok,
- bool warn)
+static bool find_symbol(struct find_symbol_arg *fsa)
{
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
@@ -556,19 +551,14 @@ static const struct kernel_symbol *find_symbol(const char *name,
GPL_ONLY, true },
#endif
};
- struct find_symbol_arg fsa = {
- .name = name,
- .gplok = gplok,
- .warn = warn,
- };
struct module *mod;
unsigned int i;
module_assert_mutex_or_preempt();
for (i = 0; i < ARRAY_SIZE(arr); i++)
- if (find_exported_symbol_in_section(&arr[i], NULL, &fsa))
- goto found;
+ if (find_exported_symbol_in_section(&arr[i], NULL, fsa))
+ return true;
list_for_each_entry_rcu(mod, &modules, list,
lockdep_is_held(&module_mutex)) {
@@ -598,21 +588,12 @@ static const struct kernel_symbol *find_symbol(const char *name,
continue;
for (i = 0; i < ARRAY_SIZE(arr); i++)
- if (find_exported_symbol_in_section(&arr[i], mod, &fsa))
- goto found;
+ if (find_exported_symbol_in_section(&arr[i], mod, fsa))
+ return true;
}
- pr_debug("Failed to find symbol %s\n", name);
- return NULL;
-
-found:
- if (owner)
- *owner = fsa.owner;
- if (crc)
- *crc = fsa.crc;
- if (license)
- *license = fsa.license;
- return fsa.sym;
+ pr_debug("Failed to find symbol %s\n", fsa->name);
+ return false;
}
/*
@@ -1074,12 +1055,15 @@ static inline void print_unload_info(struct seq_file *m, struct module *mod)
void __symbol_put(const char *symbol)
{
- struct module *owner;
+ struct find_symbol_arg fsa = {
+ .name = symbol,
+ .gplok = true,
+ };
preempt_disable();
- if (!find_symbol(symbol, &owner, NULL, NULL, true, false))
+ if (!find_symbol(&fsa))
BUG();
- module_put(owner);
+ module_put(fsa.owner);
preempt_enable();
}
EXPORT_SYMBOL(__symbol_put);
@@ -1348,19 +1332,22 @@ static int check_version(const struct load_info *info,
static inline int check_modstruct_version(const struct load_info *info,
struct module *mod)
{
- const s32 *crc;
+ struct find_symbol_arg fsa = {
+ .name = "module_layout",
+ .gplok = true,
+ };
/*
* Since this should be found in kernel (which can't be removed), no
* locking is necessary -- use preempt_disable() to placate lockdep.
*/
preempt_disable();
- if (!find_symbol("module_layout", NULL, &crc, NULL, true, false)) {
+ if (!find_symbol(&fsa)) {
preempt_enable();
BUG();
}
preempt_enable();
- return check_version(info, "module_layout", mod, crc);
+ return check_version(info, "module_layout", mod, fsa.crc);
}
/* First part is kernel version, which we ignore if module has crcs. */
@@ -1454,10 +1441,11 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
const char *name,
char ownername[])
{
- struct module *owner;
- const struct kernel_symbol *sym;
- const s32 *crc;
- enum mod_license license;
+ struct find_symbol_arg fsa = {
+ .name = name,
+ .gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
+ .warn = true,
+ };
int err;
/*
@@ -1467,42 +1455,40 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod,
*/
sched_annotate_sleep();
mutex_lock(&module_mutex);
- sym = find_symbol(name, &owner, &crc, &license,
- !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
- if (!sym)
+ if (!find_symbol(&fsa))
goto unlock;
- if (license == GPL_ONLY)
+ if (fsa.license == GPL_ONLY)
mod->using_gplonly_symbols = true;
- if (!inherit_taint(mod, owner)) {
- sym = NULL;
+ if (!inherit_taint(mod, fsa.owner)) {
+ fsa.sym = NULL;
goto getname;
}
- if (!check_version(info, name, mod, crc)) {
- sym = ERR_PTR(-EINVAL);
+ if (!check_version(info, name, mod, fsa.crc)) {
+ fsa.sym = ERR_PTR(-EINVAL);
goto getname;
}
- err = verify_namespace_is_imported(info, sym, mod);
+ err = verify_namespace_is_imported(info, fsa.sym, mod);
if (err) {
- sym = ERR_PTR(err);
+ fsa.sym = ERR_PTR(err);
goto getname;
}
- err = ref_module(mod, owner);
+ err = ref_module(mod, fsa.owner);
if (err) {
- sym = ERR_PTR(err);
+ fsa.sym = ERR_PTR(err);
goto getname;
}
getname:
/* We must make copy under the lock if we failed to get ref. */
- strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
+ strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
unlock:
mutex_unlock(&module_mutex);
- return sym;
+ return fsa.sym;
}
static const struct kernel_symbol *
@@ -2263,16 +2249,19 @@ static void free_module(struct module *mod)
void *__symbol_get(const char *symbol)
{
- struct module *owner;
- const struct kernel_symbol *sym;
+ struct find_symbol_arg fsa = {
+ .name = symbol,
+ .gplok = true,
+ .warn = true,
+ };
preempt_disable();
- sym = find_symbol(symbol, &owner, NULL, NULL, true, true);
- if (sym && strong_try_module_get(owner))
- sym = NULL;
+ if (!find_symbol(&fsa) || !strong_try_module_get(fsa.owner)) {
+ preempt_enable();
+ return NULL;
+ }
preempt_enable();
-
- return sym ? (void *)kernel_symbol_value(sym) : NULL;
+ return (void *)kernel_symbol_value(fsa.sym);
}
EXPORT_SYMBOL_GPL(__symbol_get);
@@ -2285,7 +2274,6 @@ EXPORT_SYMBOL_GPL(__symbol_get);
static int verify_exported_symbols(struct module *mod)
{
unsigned int i;
- struct module *owner;
const struct kernel_symbol *s;
struct {
const struct kernel_symbol *sym;
@@ -2302,12 +2290,15 @@ static int verify_exported_symbols(struct module *mod)
for (i = 0; i < ARRAY_SIZE(arr); i++) {
for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
- if (find_symbol(kernel_symbol_name(s), &owner, NULL,
- NULL, true, false)) {
+ struct find_symbol_arg fsa = {
+ .name = kernel_symbol_name(s),
+ .gplok = true,
+ };
+ if (find_symbol(&fsa)) {
pr_err("%s: exports duplicate symbol %s"
" (owned by %s)\n",
mod->name, kernel_symbol_name(s),
- module_name(owner));
+ module_name(fsa.owner));
return -ENOEXEC;
}
}
--
2.29.2
^ permalink raw reply related
* [PATCH 12/13] module: remove EXPORT_SYMBOL_GPL_FUTURE
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
As far as I can tell this has never been used at all, and certainly
not any time recently.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/x86/tools/relocs.c | 4 ++--
include/asm-generic/vmlinux.lds.h | 14 --------------
include/linux/export.h | 1 -
include/linux/module.h | 5 -----
kernel/module.c | 29 ++---------------------------
scripts/mod/modpost.c | 13 +------------
scripts/mod/modpost.h | 1 -
scripts/module.lds.S | 2 --
tools/include/linux/export.h | 1 -
9 files changed, 5 insertions(+), 65 deletions(-)
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index ce7188cbdae58a..0d210d0e83e241 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -61,8 +61,8 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
"__(start|end)_pci_.*|"
"__(start|end)_builtin_fw|"
- "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl|_gpl_future)|"
- "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl|_gpl_future)|"
+ "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl)|"
+ "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl)|"
"__(start|stop)___param|"
"__(start|stop)___modver|"
"__(start|stop)___bug_table|"
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index b2b3d81b1535a5..83243506e68b00 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -495,13 +495,6 @@
__stop___ksymtab_unused_gpl = .; \
} \
\
- /* Kernel symbol table: GPL-future-only symbols */ \
- __ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
- __start___ksymtab_gpl_future = .; \
- KEEP(*(SORT(___ksymtab_gpl_future+*))) \
- __stop___ksymtab_gpl_future = .; \
- } \
- \
/* Kernel symbol table: Normal symbols */ \
__kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \
__start___kcrctab = .; \
@@ -530,13 +523,6 @@
__stop___kcrctab_unused_gpl = .; \
} \
\
- /* Kernel symbol table: GPL-future-only symbols */ \
- __kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
- __start___kcrctab_gpl_future = .; \
- KEEP(*(SORT(___kcrctab_gpl_future+*))) \
- __stop___kcrctab_gpl_future = .; \
- } \
- \
/* Kernel symbol table: strings */ \
__ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
*(__ksymtab_strings) \
diff --git a/include/linux/export.h b/include/linux/export.h
index fceb5e85571711..362b64f8d4a7c2 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -157,7 +157,6 @@ struct kernel_symbol {
#define EXPORT_SYMBOL(sym) _EXPORT_SYMBOL(sym, "")
#define EXPORT_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_gpl")
-#define EXPORT_SYMBOL_GPL_FUTURE(sym) _EXPORT_SYMBOL(sym, "_gpl_future")
#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", #ns)
#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "_gpl", #ns)
diff --git a/include/linux/module.h b/include/linux/module.h
index da0f5966ee80c9..e6e50ee3041238 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -411,11 +411,6 @@ struct module {
bool async_probe_requested;
- /* symbols that will be GPL-only in the near future. */
- const struct kernel_symbol *gpl_future_syms;
- const s32 *gpl_future_crcs;
- unsigned int num_gpl_future_syms;
-
/* Exception table */
unsigned int num_exentries;
struct exception_table_entry *extable;
diff --git a/kernel/module.c b/kernel/module.c
index 7a4bce8507b96f..c987e2f42e1ad5 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -408,11 +408,8 @@ extern const struct kernel_symbol __start___ksymtab[];
extern const struct kernel_symbol __stop___ksymtab[];
extern const struct kernel_symbol __start___ksymtab_gpl[];
extern const struct kernel_symbol __stop___ksymtab_gpl[];
-extern const struct kernel_symbol __start___ksymtab_gpl_future[];
-extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
extern const s32 __start___kcrctab[];
extern const s32 __start___kcrctab_gpl[];
-extern const s32 __start___kcrctab_gpl_future[];
#ifdef CONFIG_UNUSED_SYMBOLS
extern const struct kernel_symbol __start___ksymtab_unused[];
extern const struct kernel_symbol __stop___ksymtab_unused[];
@@ -434,7 +431,6 @@ struct symsearch {
enum mod_license {
NOT_GPL_ONLY,
GPL_ONLY,
- WILL_BE_GPL_ONLY,
} license;
bool unused;
};
@@ -458,15 +454,8 @@ static bool check_exported_symbol(const struct symsearch *syms,
{
struct find_symbol_arg *fsa = data;
- if (!fsa->gplok) {
- if (syms->license == GPL_ONLY)
- return false;
- if (syms->license == WILL_BE_GPL_ONLY && fsa->warn) {
- pr_warn("Symbol %s is being used by a non-GPL module, "
- "which will not be allowed in the future\n",
- fsa->name);
- }
- }
+ if (!fsa->gplok && syms->license == GPL_ONLY)
+ return false;
#ifdef CONFIG_UNUSED_SYMBOLS
if (syms->unused && fsa->warn) {
@@ -550,9 +539,6 @@ static bool find_symbol(struct find_symbol_arg *fsa)
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
__start___kcrctab_gpl,
GPL_ONLY, false },
- { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
- __start___kcrctab_gpl_future,
- WILL_BE_GPL_ONLY, false },
#ifdef CONFIG_UNUSED_SYMBOLS
{ __start___ksymtab_unused, __stop___ksymtab_unused,
__start___kcrctab_unused,
@@ -579,10 +565,6 @@ static bool find_symbol(struct find_symbol_arg *fsa)
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
mod->gpl_crcs,
GPL_ONLY, false },
- { mod->gpl_future_syms,
- mod->gpl_future_syms + mod->num_gpl_future_syms,
- mod->gpl_future_crcs,
- WILL_BE_GPL_ONLY, false },
#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms,
mod->unused_syms + mod->num_unused_syms,
@@ -2292,7 +2274,6 @@ static int verify_exported_symbols(struct module *mod)
} arr[] = {
{ mod->syms, mod->num_syms },
{ mod->gpl_syms, mod->num_gpl_syms },
- { mod->gpl_future_syms, mod->num_gpl_future_syms },
#ifdef CONFIG_UNUSED_SYMBOLS
{ mod->unused_syms, mod->num_unused_syms },
{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
@@ -3210,11 +3191,6 @@ static int find_module_sections(struct module *mod, struct load_info *info)
sizeof(*mod->gpl_syms),
&mod->num_gpl_syms);
mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
- mod->gpl_future_syms = section_objs(info,
- "__ksymtab_gpl_future",
- sizeof(*mod->gpl_future_syms),
- &mod->num_gpl_future_syms);
- mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
#ifdef CONFIG_UNUSED_SYMBOLS
mod->unused_syms = section_objs(info, "__ksymtab_unused",
@@ -3408,7 +3384,6 @@ static int check_module_license_and_versions(struct module *mod)
#ifdef CONFIG_MODVERSIONS
if ((mod->num_syms && !mod->crcs)
|| (mod->num_gpl_syms && !mod->gpl_crcs)
- || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
#ifdef CONFIG_UNUSED_SYMBOLS
|| (mod->num_unused_syms && !mod->unused_crcs)
|| (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index d6c81657d69550..25c1446055d16b 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -44,7 +44,7 @@ static bool error_occurred;
enum export {
export_plain, export_unused, export_gpl,
- export_unused_gpl, export_gpl_future, export_unknown
+ export_unused_gpl, export_unknown
};
/* In kernel, this size is defined in linux/module.h;
@@ -304,7 +304,6 @@ static const struct {
{ .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
{ .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
{ .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
- { .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
{ .str = "(unknown)", .export = export_unknown },
};
@@ -369,8 +368,6 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
return export_gpl;
else if (strstarts(secname, "___ksymtab_unused_gpl+"))
return export_unused_gpl;
- else if (strstarts(secname, "___ksymtab_gpl_future+"))
- return export_gpl_future;
else
return export_unknown;
}
@@ -385,8 +382,6 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
return export_gpl;
else if (sec == elf->export_unused_gpl_sec)
return export_unused_gpl;
- else if (sec == elf->export_gpl_future_sec)
- return export_gpl_future;
else
return export_unknown;
}
@@ -596,8 +591,6 @@ static int parse_elf(struct elf_info *info, const char *filename)
info->export_gpl_sec = i;
else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
info->export_unused_gpl_sec = i;
- else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
- info->export_gpl_future_sec = i;
if (sechdrs[i].sh_type == SHT_SYMTAB) {
unsigned int sh_link_idx;
@@ -2152,10 +2145,6 @@ static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
error("GPL-incompatible module %s.ko uses GPL-only symbol marked UNUSED '%s'\n",
m, s);
break;
- case export_gpl_future:
- warn("GPL-incompatible module %s.ko uses future GPL-only symbol '%s'\n",
- m, s);
- break;
case export_plain:
case export_unused:
case export_unknown:
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index e6f46eee0af02f..834220de002bd1 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -142,7 +142,6 @@ struct elf_info {
Elf_Section export_unused_sec;
Elf_Section export_gpl_sec;
Elf_Section export_unused_gpl_sec;
- Elf_Section export_gpl_future_sec;
char *strtab;
char *modinfo;
unsigned int modinfo_len;
diff --git a/scripts/module.lds.S b/scripts/module.lds.S
index 69b9b71a6a4731..d82b452e8a7168 100644
--- a/scripts/module.lds.S
+++ b/scripts/module.lds.S
@@ -13,12 +13,10 @@ SECTIONS {
__ksymtab_gpl 0 : { *(SORT(___ksymtab_gpl+*)) }
__ksymtab_unused 0 : { *(SORT(___ksymtab_unused+*)) }
__ksymtab_unused_gpl 0 : { *(SORT(___ksymtab_unused_gpl+*)) }
- __ksymtab_gpl_future 0 : { *(SORT(___ksymtab_gpl_future+*)) }
__kcrctab 0 : { *(SORT(___kcrctab+*)) }
__kcrctab_gpl 0 : { *(SORT(___kcrctab_gpl+*)) }
__kcrctab_unused 0 : { *(SORT(___kcrctab_unused+*)) }
__kcrctab_unused_gpl 0 : { *(SORT(___kcrctab_unused_gpl+*)) }
- __kcrctab_gpl_future 0 : { *(SORT(___kcrctab_gpl_future+*)) }
.init_array 0 : ALIGN(8) { *(SORT(.init_array.*)) *(.init_array) }
diff --git a/tools/include/linux/export.h b/tools/include/linux/export.h
index d07e586b9ba0ec..9f61349a8944e1 100644
--- a/tools/include/linux/export.h
+++ b/tools/include/linux/export.h
@@ -3,7 +3,6 @@
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
-#define EXPORT_SYMBOL_GPL_FUTURE(sym)
#define EXPORT_UNUSED_SYMBOL(sym)
#define EXPORT_UNUSED_SYMBOL_GPL(sym)
--
2.29.2
^ permalink raw reply related
* [PATCH 13/13] module: remove EXPORT_UNUSED_SYMBOL*
From: Christoph Hellwig @ 2021-02-02 12:13 UTC (permalink / raw)
To: Frederic Barrat, Andrew Donnellan, Maarten Lankhorst,
Maxime Ripard, Thomas Zimmermann, David Airlie, Daniel Vetter,
Jessica Yu, Josh Poimboeuf, Jiri Kosina, Miroslav Benes,
Petr Mladek, Joe Lawrence
Cc: Michal Marek, linux-kbuild, Masahiro Yamada, linux-kernel,
dri-devel, live-patching, linuxppc-dev
In-Reply-To: <20210202121334.1361503-1-hch@lst.de>
EXPORT_UNUSED_SYMBOL* is not actually used anywhere. Remove the
unused functionality as we generally just remove unused code anyway.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/arm/configs/bcm2835_defconfig | 1 -
arch/arm/configs/mxs_defconfig | 1 -
arch/mips/configs/nlm_xlp_defconfig | 1 -
arch/mips/configs/nlm_xlr_defconfig | 1 -
arch/parisc/configs/generic-32bit_defconfig | 1 -
arch/parisc/configs/generic-64bit_defconfig | 1 -
arch/powerpc/configs/ppc6xx_defconfig | 1 -
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
arch/sh/configs/edosk7760_defconfig | 1 -
arch/sh/configs/sdk7780_defconfig | 1 -
arch/x86/configs/i386_defconfig | 1 -
arch/x86/configs/x86_64_defconfig | 1 -
arch/x86/tools/relocs.c | 4 +-
include/asm-generic/vmlinux.lds.h | 28 --------
include/linux/export.h | 8 ---
include/linux/module.h | 12 ----
init/Kconfig | 17 -----
kernel/module.c | 71 ++-------------------
scripts/checkpatch.pl | 6 +-
scripts/mod/modpost.c | 39 +----------
scripts/mod/modpost.h | 2 -
scripts/module.lds.S | 4 --
tools/include/linux/export.h | 2 -
24 files changed, 13 insertions(+), 193 deletions(-)
diff --git a/arch/arm/configs/bcm2835_defconfig b/arch/arm/configs/bcm2835_defconfig
index 44ff9cd88d8161..d6c6c2e031c43a 100644
--- a/arch/arm/configs/bcm2835_defconfig
+++ b/arch/arm/configs/bcm2835_defconfig
@@ -177,7 +177,6 @@ CONFIG_BOOT_PRINTK_DELAY=y
CONFIG_DYNAMIC_DEBUG=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_LOCKUP_DETECTOR=y
CONFIG_SCHED_TRACER=y
diff --git a/arch/arm/configs/mxs_defconfig b/arch/arm/configs/mxs_defconfig
index a9c6f32a9b1c9d..ca32446b187f5d 100644
--- a/arch/arm/configs/mxs_defconfig
+++ b/arch/arm/configs/mxs_defconfig
@@ -164,7 +164,6 @@ CONFIG_FONTS=y
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
CONFIG_FRAME_WARN=2048
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
CONFIG_SOFTLOCKUP_DETECTOR=y
diff --git a/arch/mips/configs/nlm_xlp_defconfig b/arch/mips/configs/nlm_xlp_defconfig
index 72a211d2d556fd..32c29061172325 100644
--- a/arch/mips/configs/nlm_xlp_defconfig
+++ b/arch/mips/configs/nlm_xlp_defconfig
@@ -549,7 +549,6 @@ CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_FRAME_WARN=1024
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_DETECT_HUNG_TASK=y
CONFIG_SCHEDSTATS=y
diff --git a/arch/mips/configs/nlm_xlr_defconfig b/arch/mips/configs/nlm_xlr_defconfig
index 4ecb157e56d427..bf9b9244929ecd 100644
--- a/arch/mips/configs/nlm_xlr_defconfig
+++ b/arch/mips/configs/nlm_xlr_defconfig
@@ -500,7 +500,6 @@ CONFIG_CRC7=m
CONFIG_PRINTK_TIME=y
CONFIG_DEBUG_INFO=y
# CONFIG_ENABLE_MUST_CHECK is not set
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_MEMORY_INIT=y
CONFIG_DETECT_HUNG_TASK=y
CONFIG_SCHEDSTATS=y
diff --git a/arch/parisc/configs/generic-32bit_defconfig b/arch/parisc/configs/generic-32bit_defconfig
index 3cbcfad5f7249d..7611d48c599e01 100644
--- a/arch/parisc/configs/generic-32bit_defconfig
+++ b/arch/parisc/configs/generic-32bit_defconfig
@@ -22,7 +22,6 @@ CONFIG_PCI_LBA=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-CONFIG_UNUSED_SYMBOLS=y
# CONFIG_BLK_DEV_BSG is not set
# CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set
CONFIG_BINFMT_MISC=m
diff --git a/arch/parisc/configs/generic-64bit_defconfig b/arch/parisc/configs/generic-64bit_defconfig
index 8f81fcbf04c413..53054b81461a10 100644
--- a/arch/parisc/configs/generic-64bit_defconfig
+++ b/arch/parisc/configs/generic-64bit_defconfig
@@ -31,7 +31,6 @@ CONFIG_MODULE_FORCE_LOAD=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_INTEGRITY=y
CONFIG_BINFMT_MISC=m
# CONFIG_COMPACTION is not set
diff --git a/arch/powerpc/configs/ppc6xx_defconfig b/arch/powerpc/configs/ppc6xx_defconfig
index ef09f3cce1fa85..34c3859040f9f7 100644
--- a/arch/powerpc/configs/ppc6xx_defconfig
+++ b/arch/powerpc/configs/ppc6xx_defconfig
@@ -1072,7 +1072,6 @@ CONFIG_NLS_ISO8859_15=m
CONFIG_NLS_KOI8_R=m
CONFIG_NLS_KOI8_U=m
CONFIG_DEBUG_INFO=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_HEADERS_INSTALL=y
CONFIG_MAGIC_SYSRQ=y
CONFIG_DEBUG_KERNEL=y
diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index c4f6ff98a612cd..58e54d17e3154b 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -71,7 +71,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
CONFIG_MODULE_SRCVERSION_ALL=y
CONFIG_MODULE_SIG_SHA256=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_INTEGRITY=y
CONFIG_BLK_DEV_THROTTLING=y
CONFIG_BLK_WBT=y
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 51135893cffe34..b5e62c0d3e23e0 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -66,7 +66,6 @@ CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_MODVERSIONS=y
CONFIG_MODULE_SRCVERSION_ALL=y
CONFIG_MODULE_SIG_SHA256=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_BLK_DEV_THROTTLING=y
CONFIG_BLK_WBT=y
CONFIG_BLK_CGROUP_IOLATENCY=y
diff --git a/arch/sh/configs/edosk7760_defconfig b/arch/sh/configs/edosk7760_defconfig
index 02ba622985769d..d77f54e906fd04 100644
--- a/arch/sh/configs/edosk7760_defconfig
+++ b/arch/sh/configs/edosk7760_defconfig
@@ -102,7 +102,6 @@ CONFIG_NLS_UTF8=y
CONFIG_PRINTK_TIME=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_MAGIC_SYSRQ=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DEBUG_SHIRQ=y
CONFIG_DETECT_HUNG_TASK=y
diff --git a/arch/sh/configs/sdk7780_defconfig b/arch/sh/configs/sdk7780_defconfig
index d00376eb044f8a..6c719ab4332ac9 100644
--- a/arch/sh/configs/sdk7780_defconfig
+++ b/arch/sh/configs/sdk7780_defconfig
@@ -128,7 +128,6 @@ CONFIG_NLS_ISO8859_15=y
CONFIG_NLS_UTF8=y
# CONFIG_ENABLE_MUST_CHECK is not set
CONFIG_MAGIC_SYSRQ=y
-CONFIG_UNUSED_SYMBOLS=y
CONFIG_DEBUG_KERNEL=y
CONFIG_DETECT_HUNG_TASK=y
# CONFIG_SCHED_DEBUG is not set
diff --git a/arch/x86/configs/i386_defconfig b/arch/x86/configs/i386_defconfig
index 78210793d357cf..9c9c4a888b1dbf 100644
--- a/arch/x86/configs/i386_defconfig
+++ b/arch/x86/configs/i386_defconfig
@@ -50,7 +50,6 @@ CONFIG_JUMP_LABEL=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-# CONFIG_UNUSED_SYMBOLS is not set
CONFIG_BINFMT_MISC=y
CONFIG_NET=y
CONFIG_PACKET=y
diff --git a/arch/x86/configs/x86_64_defconfig b/arch/x86/configs/x86_64_defconfig
index 9936528e19393a..b60bd2d8603499 100644
--- a/arch/x86/configs/x86_64_defconfig
+++ b/arch/x86/configs/x86_64_defconfig
@@ -48,7 +48,6 @@ CONFIG_JUMP_LABEL=y
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
-# CONFIG_UNUSED_SYMBOLS is not set
CONFIG_BINFMT_MISC=y
CONFIG_NET=y
CONFIG_PACKET=y
diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 0d210d0e83e241..b9c577a3cacca6 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -61,8 +61,8 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"(__iommu_table|__apicdrivers|__smp_locks)(|_end)|"
"__(start|end)_pci_.*|"
"__(start|end)_builtin_fw|"
- "__(start|stop)___ksymtab(|_gpl|_unused|_unused_gpl)|"
- "__(start|stop)___kcrctab(|_gpl|_unused|_unused_gpl)|"
+ "__(start|stop)___ksymtab(|_gpl)|"
+ "__(start|stop)___kcrctab(|_gpl)|"
"__(start|stop)___param|"
"__(start|stop)___modver|"
"__(start|stop)___bug_table|"
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index 83243506e68b00..1fa338ac6a5477 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -481,20 +481,6 @@
__stop___ksymtab_gpl = .; \
} \
\
- /* Kernel symbol table: Normal unused symbols */ \
- __ksymtab_unused : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) { \
- __start___ksymtab_unused = .; \
- KEEP(*(SORT(___ksymtab_unused+*))) \
- __stop___ksymtab_unused = .; \
- } \
- \
- /* Kernel symbol table: GPL-only unused symbols */ \
- __ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
- __start___ksymtab_unused_gpl = .; \
- KEEP(*(SORT(___ksymtab_unused_gpl+*))) \
- __stop___ksymtab_unused_gpl = .; \
- } \
- \
/* Kernel symbol table: Normal symbols */ \
__kcrctab : AT(ADDR(__kcrctab) - LOAD_OFFSET) { \
__start___kcrctab = .; \
@@ -509,20 +495,6 @@
__stop___kcrctab_gpl = .; \
} \
\
- /* Kernel symbol table: Normal unused symbols */ \
- __kcrctab_unused : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) { \
- __start___kcrctab_unused = .; \
- KEEP(*(SORT(___kcrctab_unused+*))) \
- __stop___kcrctab_unused = .; \
- } \
- \
- /* Kernel symbol table: GPL-only unused symbols */ \
- __kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
- __start___kcrctab_unused_gpl = .; \
- KEEP(*(SORT(___kcrctab_unused_gpl+*))) \
- __stop___kcrctab_unused_gpl = .; \
- } \
- \
/* Kernel symbol table: strings */ \
__ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) { \
*(__ksymtab_strings) \
diff --git a/include/linux/export.h b/include/linux/export.h
index 362b64f8d4a7c2..6271a5d9c988fa 100644
--- a/include/linux/export.h
+++ b/include/linux/export.h
@@ -160,14 +160,6 @@ struct kernel_symbol {
#define EXPORT_SYMBOL_NS(sym, ns) __EXPORT_SYMBOL(sym, "", #ns)
#define EXPORT_SYMBOL_NS_GPL(sym, ns) __EXPORT_SYMBOL(sym, "_gpl", #ns)
-#ifdef CONFIG_UNUSED_SYMBOLS
-#define EXPORT_UNUSED_SYMBOL(sym) _EXPORT_SYMBOL(sym, "_unused")
-#define EXPORT_UNUSED_SYMBOL_GPL(sym) _EXPORT_SYMBOL(sym, "_unused_gpl")
-#else
-#define EXPORT_UNUSED_SYMBOL(sym)
-#define EXPORT_UNUSED_SYMBOL_GPL(sym)
-#endif
-
#endif /* !__ASSEMBLY__ */
#endif /* _LINUX_EXPORT_H */
diff --git a/include/linux/module.h b/include/linux/module.h
index e6e50ee3041238..59f094fa6f7441 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -392,18 +392,6 @@ struct module {
const s32 *gpl_crcs;
bool using_gplonly_symbols;
-#ifdef CONFIG_UNUSED_SYMBOLS
- /* unused exported symbols. */
- const struct kernel_symbol *unused_syms;
- const s32 *unused_crcs;
- unsigned int num_unused_syms;
-
- /* GPL-only, unused exported symbols. */
- unsigned int num_unused_gpl_syms;
- const struct kernel_symbol *unused_gpl_syms;
- const s32 *unused_gpl_crcs;
-#endif
-
#ifdef CONFIG_MODULE_SIG
/* Signature was verified. */
bool sig_ok;
diff --git a/init/Kconfig b/init/Kconfig
index b77c60f8b963d4..11b803b45c1995 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -2262,25 +2262,8 @@ config MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
If unsure, say N.
-config UNUSED_SYMBOLS
- bool "Enable unused/obsolete exported symbols"
- default y if X86
- help
- Unused but exported symbols make the kernel needlessly bigger. For
- that reason most of these unused exports will soon be removed. This
- option is provided temporarily to provide a transition period in case
- some external kernel module needs one of these symbols anyway. If you
- encounter such a case in your module, consider if you are actually
- using the right API. (rationale: since nobody in the kernel is using
- this in a module, there is a pretty good chance it's actually the
- wrong interface to use). If you really need the symbol, please send a
- mail to the linux kernel mailing list mentioning the symbol and why
- you really need it, and what the merge plan to the mainline kernel for
- your module is.
-
config TRIM_UNUSED_KSYMS
bool "Trim unused exported kernel symbols"
- depends on !UNUSED_SYMBOLS
help
The kernel and some modules make many symbols available for
other modules to use via EXPORT_SYMBOL() and variants. Depending
diff --git a/kernel/module.c b/kernel/module.c
index c987e2f42e1ad5..d769fc2959a3e4 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -410,14 +410,6 @@ extern const struct kernel_symbol __start___ksymtab_gpl[];
extern const struct kernel_symbol __stop___ksymtab_gpl[];
extern const s32 __start___kcrctab[];
extern const s32 __start___kcrctab_gpl[];
-#ifdef CONFIG_UNUSED_SYMBOLS
-extern const struct kernel_symbol __start___ksymtab_unused[];
-extern const struct kernel_symbol __stop___ksymtab_unused[];
-extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
-extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
-extern const s32 __start___kcrctab_unused[];
-extern const s32 __start___kcrctab_unused_gpl[];
-#endif
#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
@@ -432,7 +424,6 @@ struct symsearch {
NOT_GPL_ONLY,
GPL_ONLY,
} license;
- bool unused;
};
struct find_symbol_arg {
@@ -456,19 +447,6 @@ static bool check_exported_symbol(const struct symsearch *syms,
if (!fsa->gplok && syms->license == GPL_ONLY)
return false;
-
-#ifdef CONFIG_UNUSED_SYMBOLS
- if (syms->unused && fsa->warn) {
- pr_warn("Symbol %s is marked as UNUSED, however this module is "
- "using it.\n", fsa->name);
- pr_warn("This symbol will go away in the future.\n");
- pr_warn("Please evaluate if this is the right api to use and "
- "if it really is, submit a report to the linux kernel "
- "mailing list together with submitting your code for "
- "inclusion.\n");
- }
-#endif
-
fsa->owner = owner;
fsa->crc = symversion(syms->crcs, symnum);
fsa->sym = &syms->start[symnum];
@@ -535,18 +513,10 @@ static bool find_symbol(struct find_symbol_arg *fsa)
{
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
- NOT_GPL_ONLY, false },
+ NOT_GPL_ONLY },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
__start___kcrctab_gpl,
- GPL_ONLY, false },
-#ifdef CONFIG_UNUSED_SYMBOLS
- { __start___ksymtab_unused, __stop___ksymtab_unused,
- __start___kcrctab_unused,
- NOT_GPL_ONLY, true },
- { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
- __start___kcrctab_unused_gpl,
- GPL_ONLY, true },
-#endif
+ GPL_ONLY },
};
struct module *mod;
unsigned int i;
@@ -561,20 +531,10 @@ static bool find_symbol(struct find_symbol_arg *fsa)
lockdep_is_held(&module_mutex)) {
struct symsearch arr[] = {
{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
- NOT_GPL_ONLY, false },
+ NOT_GPL_ONLY },
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
mod->gpl_crcs,
- GPL_ONLY, false },
-#ifdef CONFIG_UNUSED_SYMBOLS
- { mod->unused_syms,
- mod->unused_syms + mod->num_unused_syms,
- mod->unused_crcs,
- NOT_GPL_ONLY, true },
- { mod->unused_gpl_syms,
- mod->unused_gpl_syms + mod->num_unused_gpl_syms,
- mod->unused_gpl_crcs,
- GPL_ONLY, true },
-#endif
+ GPL_ONLY },
};
if (mod->state == MODULE_STATE_UNFORMED)
@@ -2274,10 +2234,6 @@ static int verify_exported_symbols(struct module *mod)
} arr[] = {
{ mod->syms, mod->num_syms },
{ mod->gpl_syms, mod->num_gpl_syms },
-#ifdef CONFIG_UNUSED_SYMBOLS
- { mod->unused_syms, mod->num_unused_syms },
- { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
-#endif
};
for (i = 0; i < ARRAY_SIZE(arr); i++) {
@@ -3192,16 +3148,6 @@ static int find_module_sections(struct module *mod, struct load_info *info)
&mod->num_gpl_syms);
mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
-#ifdef CONFIG_UNUSED_SYMBOLS
- mod->unused_syms = section_objs(info, "__ksymtab_unused",
- sizeof(*mod->unused_syms),
- &mod->num_unused_syms);
- mod->unused_crcs = section_addr(info, "__kcrctab_unused");
- mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
- sizeof(*mod->unused_gpl_syms),
- &mod->num_unused_gpl_syms);
- mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
-#endif
#ifdef CONFIG_CONSTRUCTORS
mod->ctors = section_objs(info, ".ctors",
sizeof(*mod->ctors), &mod->num_ctors);
@@ -3382,13 +3328,8 @@ static int check_module_license_and_versions(struct module *mod)
pr_warn("%s: module license taints kernel.\n", mod->name);
#ifdef CONFIG_MODVERSIONS
- if ((mod->num_syms && !mod->crcs)
- || (mod->num_gpl_syms && !mod->gpl_crcs)
-#ifdef CONFIG_UNUSED_SYMBOLS
- || (mod->num_unused_syms && !mod->unused_crcs)
- || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
-#endif
- ) {
+ if ((mod->num_syms && !mod->crcs) ||
+ (mod->num_gpl_syms && !mod->gpl_crcs)) {
return try_to_force_load(mod,
"no versions for exported symbols");
}
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 92e888ed939f98..eabd2d5467b156 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4290,8 +4290,7 @@ sub process {
if (defined $realline_next &&
exists $lines[$realline_next - 1] &&
!defined $suppress_export{$realline_next} &&
- ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
- $lines[$realline_next - 1] =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
+ ($lines[$realline_next - 1] =~ /EXPORT_SYMBOL.*\((.*)\)/)) {
# Handle definitions which produce identifiers with
# a prefix:
# XXX(foo);
@@ -4318,8 +4317,7 @@ sub process {
}
if (!defined $suppress_export{$linenr} &&
$prevline =~ /^.\s*$/ &&
- ($line =~ /EXPORT_SYMBOL.*\((.*)\)/ ||
- $line =~ /EXPORT_UNUSED_SYMBOL.*\((.*)\)/)) {
+ ($line =~ /EXPORT_SYMBOL.*\((.*)\)/)) {
#print "FOO B <$lines[$linenr - 1]>\n";
$suppress_export{$linenr} = 2;
}
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 25c1446055d16b..20fc57837881ab 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -43,8 +43,9 @@ static int allow_missing_ns_imports;
static bool error_occurred;
enum export {
- export_plain, export_unused, export_gpl,
- export_unused_gpl, export_unknown
+ export_plain,
+ export_gpl,
+ export_unknown
};
/* In kernel, this size is defined in linux/module.h;
@@ -301,9 +302,7 @@ static const struct {
enum export export;
} export_list[] = {
{ .str = "EXPORT_SYMBOL", .export = export_plain },
- { .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
{ .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
- { .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
{ .str = "(unknown)", .export = export_unknown },
};
@@ -362,12 +361,8 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
if (strstarts(secname, "___ksymtab+"))
return export_plain;
- else if (strstarts(secname, "___ksymtab_unused+"))
- return export_unused;
else if (strstarts(secname, "___ksymtab_gpl+"))
return export_gpl;
- else if (strstarts(secname, "___ksymtab_unused_gpl+"))
- return export_unused_gpl;
else
return export_unknown;
}
@@ -376,12 +371,8 @@ static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
{
if (sec == elf->export_sec)
return export_plain;
- else if (sec == elf->export_unused_sec)
- return export_unused;
else if (sec == elf->export_gpl_sec)
return export_gpl;
- else if (sec == elf->export_unused_gpl_sec)
- return export_unused_gpl;
else
return export_unknown;
}
@@ -585,12 +576,8 @@ static int parse_elf(struct elf_info *info, const char *filename)
info->modinfo_len = sechdrs[i].sh_size;
} else if (strcmp(secname, "__ksymtab") == 0)
info->export_sec = i;
- else if (strcmp(secname, "__ksymtab_unused") == 0)
- info->export_unused_sec = i;
else if (strcmp(secname, "__ksymtab_gpl") == 0)
info->export_gpl_sec = i;
- else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
- info->export_unused_gpl_sec = i;
if (sechdrs[i].sh_type == SHT_SYMTAB) {
unsigned int sh_link_idx;
@@ -2141,32 +2128,13 @@ static void check_for_gpl_usage(enum export exp, const char *m, const char *s)
error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
m, s);
break;
- case export_unused_gpl:
- error("GPL-incompatible module %s.ko uses GPL-only symbol marked UNUSED '%s'\n",
- m, s);
- break;
case export_plain:
- case export_unused:
case export_unknown:
/* ignore */
break;
}
}
-static void check_for_unused(enum export exp, const char *m, const char *s)
-{
- switch (exp) {
- case export_unused:
- case export_unused_gpl:
- warn("module %s.ko uses symbol '%s' marked UNUSED\n",
- m, s);
- break;
- default:
- /* ignore */
- break;
- }
-}
-
static void check_exports(struct module *mod)
{
struct symbol *s, *exp;
@@ -2197,7 +2165,6 @@ static void check_exports(struct module *mod)
if (!mod->gpl_compatible)
check_for_gpl_usage(exp->export, basename, exp->name);
- check_for_unused(exp->export, basename, exp->name);
}
}
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 834220de002bd1..0c47ff95c0e227 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -139,9 +139,7 @@ struct elf_info {
Elf_Sym *symtab_start;
Elf_Sym *symtab_stop;
Elf_Section export_sec;
- Elf_Section export_unused_sec;
Elf_Section export_gpl_sec;
- Elf_Section export_unused_gpl_sec;
char *strtab;
char *modinfo;
unsigned int modinfo_len;
diff --git a/scripts/module.lds.S b/scripts/module.lds.S
index d82b452e8a7168..24e8af579ce378 100644
--- a/scripts/module.lds.S
+++ b/scripts/module.lds.S
@@ -11,12 +11,8 @@ SECTIONS {
__ksymtab 0 : { *(SORT(___ksymtab+*)) }
__ksymtab_gpl 0 : { *(SORT(___ksymtab_gpl+*)) }
- __ksymtab_unused 0 : { *(SORT(___ksymtab_unused+*)) }
- __ksymtab_unused_gpl 0 : { *(SORT(___ksymtab_unused_gpl+*)) }
__kcrctab 0 : { *(SORT(___kcrctab+*)) }
__kcrctab_gpl 0 : { *(SORT(___kcrctab_gpl+*)) }
- __kcrctab_unused 0 : { *(SORT(___kcrctab_unused+*)) }
- __kcrctab_unused_gpl 0 : { *(SORT(___kcrctab_unused_gpl+*)) }
.init_array 0 : ALIGN(8) { *(SORT(.init_array.*)) *(.init_array) }
diff --git a/tools/include/linux/export.h b/tools/include/linux/export.h
index 9f61349a8944e1..acb6f4daa2f0b4 100644
--- a/tools/include/linux/export.h
+++ b/tools/include/linux/export.h
@@ -3,7 +3,5 @@
#define EXPORT_SYMBOL(sym)
#define EXPORT_SYMBOL_GPL(sym)
-#define EXPORT_UNUSED_SYMBOL(sym)
-#define EXPORT_UNUSED_SYMBOL_GPL(sym)
#endif
--
2.29.2
^ permalink raw reply related
* [PATCH 1/2] powerpc/64: Make stack tracing work during very early boot
From: Michael Ellerman @ 2021-02-02 13:02 UTC (permalink / raw)
To: linuxppc-dev
If we try to stack trace very early during boot, either due to a
WARN/BUG or manual dump_stack(), we will oops in
valid_emergency_stack() when we try to dereference the paca_ptrs
array.
The fix is simple, we just return false if paca_ptrs isn't allocated
yet. The stack pointer definitely isn't part of any emergency stack
because we haven't allocated any yet.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/kernel/process.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 8520ed5ae144..e296440e9d16 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -2047,6 +2047,9 @@ static inline int valid_emergency_stack(unsigned long sp, struct task_struct *p,
unsigned long stack_page;
unsigned long cpu = task_cpu(p);
+ if (!paca_ptrs)
+ return 0;
+
stack_page = (unsigned long)paca_ptrs[cpu]->emergency_sp - THREAD_SIZE;
if (sp >= stack_page && sp <= stack_page + THREAD_SIZE - nbytes)
return 1;
--
2.25.1
^ permalink raw reply related
* [PATCH 2/2] powerpc/64s: Handle program checks in wrong endian during early boot
From: Michael Ellerman @ 2021-02-02 13:02 UTC (permalink / raw)
To: linuxppc-dev
In-Reply-To: <20210202130207.1303975-1-mpe@ellerman.id.au>
There's a short window during boot where although the kernel is
running little endian, any exceptions will cause the CPU to switch
back to big endian. This situation persists until we call
configure_exceptions(), which calls either the hypervisor or OPAL to
configure the CPU so that exceptions will be taken in little
endian (via HID0[HILE]).
We don't intend to take exceptions during early boot, but one way we
sometimes do is via a WARN/BUG etc. Those all boil down to a trap
instruction, which will cause a program check exception.
The first instruction of the program check handler is an mtsprg, which
when executed in the wrong endian is an lhzu with a ~3GB displacement
from r3. The content of r3 is random, so that becomes a load from some
random location, and depending on the system (installed RAM etc.) can
easily lead to a checkstop, or an infinitely recursive page fault.
That prevents whatever the WARN/BUG was complaining about being
printed to the console, and the user just sees a dead system.
We can fix it by having a trampoline at the beginning of the program
check handler that detects we are in the wrong endian, and flips us
back to the correct endian.
We can't flip MSR[LE] using mtmsr (alas), so we have to use rfid. That
requires backing up SRR0/1 as well as a GPR. To do that we use
SPRG0/2/3 (SPRG1 is already used for the paca). SPRG3 is user
readable, but this trampoline is only active very early in boot, and
SPRG3 will be reinitialised in vdso_getcpu_init() before userspace
starts.
With this trampoline in place we can survive a WARN early in boot and
print a stack trace, which is eventually printed to the console once
the console is up, eg:
[83565.758545] kexec_core: Starting new kernel
[ 0.000000] ------------[ cut here ]------------
[ 0.000000] static_key_enable_cpuslocked(): static key '0xc000000000ea6160' used before call to jump_label_init()
[ 0.000000] WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xfc/0x120
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.10.0-gcc-8.2.0-dirty #618
[ 0.000000] NIP: c0000000002fd46c LR: c0000000002fd468 CTR: c000000000170660
[ 0.000000] REGS: c000000001227940 TRAP: 0700 Not tainted (5.10.0-gcc-8.2.0-dirty)
[ 0.000000] MSR: 9000000002823003 <SF,HV,VEC,VSX,FP,ME,RI,LE> CR: 24882422 XER: 20040000
[ 0.000000] CFAR: 0000000000000730 IRQMASK: 1
[ 0.000000] GPR00: c0000000002fd468 c000000001227bd0 c000000001228300 0000000000000065
[ 0.000000] GPR04: 0000000000000001 0000000000000065 c0000000010cf970 000000000000000d
[ 0.000000] GPR08: 0000000000000000 0000000000000000 0000000000000000 c00000000122763f
[ 0.000000] GPR12: 0000000000002000 c000000000f8a980 0000000000000000 0000000000000000
[ 0.000000] GPR16: 0000000000000000 0000000000000000 c000000000f88c8e c000000000f88c9a
[ 0.000000] GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[ 0.000000] GPR24: 0000000000000000 c000000000dea3a8 0000000000000000 c000000000f35114
[ 0.000000] GPR28: 0000002800000000 c000000000f88c9a c000000000f88c8e c000000000ea6160
[ 0.000000] NIP [c0000000002fd46c] static_key_enable_cpuslocked+0xfc/0x120
[ 0.000000] LR [c0000000002fd468] static_key_enable_cpuslocked+0xf8/0x120
[ 0.000000] Call Trace:
[ 0.000000] [c000000001227bd0] [c0000000002fd468] static_key_enable_cpuslocked+0xf8/0x120 (unreliable)
[ 0.000000] [c000000001227c40] [c0000000002fd4c0] static_key_enable+0x30/0x50
[ 0.000000] [c000000001227c70] [c000000000f6629c] early_page_poison_param+0x58/0x9c
[ 0.000000] [c000000001227cb0] [c000000000f351b8] do_early_param+0xa4/0x10c
[ 0.000000] [c000000001227d30] [c00000000011e020] parse_args+0x270/0x5e0
[ 0.000000] [c000000001227e20] [c000000000f35864] parse_early_options+0x48/0x5c
[ 0.000000] [c000000001227e40] [c000000000f358d0] parse_early_param+0x58/0x84
[ 0.000000] [c000000001227e70] [c000000000f3a368] early_init_devtree+0xc4/0x490
[ 0.000000] [c000000001227f10] [c000000000f3bca0] early_setup+0xc8/0x1c8
[ 0.000000] [c000000001227f90] [000000000000c320] 0xc320
[ 0.000000] Instruction dump:
[ 0.000000] 4bfffddd 7c2004ac 39200001 913f0000 4bffffb8 7c651b78 3c82ffac 3c62ffc0
[ 0.000000] 38841b00 3863f310 4bdf03a5 60000000 <0fe00000> 4bffff38 60000000 60000000
[ 0.000000] random: get_random_bytes called from print_oops_end_marker+0x40/0x80 with crng_init=0
[ 0.000000] ---[ end trace 0000000000000000 ]---
[ 0.000000] dt-cpu-ftrs: setup for ISA 3000
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
---
arch/powerpc/kernel/exceptions-64s.S | 45 ++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index b3793f982b2b..c51c436d5845 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1630,6 +1630,51 @@ INT_DEFINE_BEGIN(program_check)
INT_DEFINE_END(program_check)
EXC_REAL_BEGIN(program_check, 0x700, 0x100)
+
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+ /*
+ * There's a short window during boot where although the kernel is
+ * running little endian, any exceptions will cause the CPU to switch
+ * back to big endian. For example a WARN() boils down to a trap
+ * instruction, which will cause a program check, and we end up here but
+ * with the CPU in big endian mode. The first instruction of the program
+ * check handler (in GEN_INT_ENTRY below) is an mtsprg, which when
+ * executed in the wrong endian is an lhzu with a ~3GB displacement from
+ * r3. The content of r3 is random, so that is a load from some random
+ * location, and depending on the system can easily lead to a checkstop,
+ * or an infinitely recursive page fault.
+ *
+ * So to handle that case we have a trampoline here that can detect we
+ * are in the wrong endian and flip us back to the correct endian. We
+ * can't flip MSR[LE] using mtmsr, so we have to use rfid. That requires
+ * backing up SRR0/1 as well as a GPR. To do that we use SPRG0/2/3, as
+ * SPRG1 is already used for the paca. SPRG3 is user readable, but this
+ * trampoline is only active very early in boot, and SPRG3 will be
+ * reinitialised in vdso_getcpu_init() before userspace starts.
+ */
+BEGIN_FTR_SECTION
+ tdi 0,0,0x48 // Trap never, or in reverse endian: b . + 8
+ b 1f // Skip trampoline if endian is correct
+ .long 0xa643707d // mtsprg 0, r11 Backup r11
+ .long 0xa6027a7d // mfsrr0 r11
+ .long 0xa643727d // mtsprg 2, r11 Backup SRR0 in SPRG2
+ .long 0xa6027b7d // mfsrr1 r11
+ .long 0xa643737d // mtsprg 3, r11 Backup SRR1 in SPRG3
+ .long 0xa600607d // mfmsr r11
+ .long 0x01006b69 // xori r11, r11, 1 Invert MSR[LE]
+ .long 0xa6037b7d // mtsrr1 r11
+ .long 0x34076039 // li r11, 0x734
+ .long 0xa6037a7d // mtsrr0 r11
+ .long 0x2400004c // rfid
+ mfsprg r11, 3
+ mtsrr1 r11 // Restore SRR1
+ mfsprg r11, 2
+ mtsrr0 r11 // Restore SRR0
+ mfsprg r11, 0 // Restore r11
+1:
+END_FTR_SECTION(0, 1) // nop out after boot
+#endif /* CONFIG_CPU_LITTLE_ENDIAN */
+
GEN_INT_ENTRY program_check, virt=0
EXC_REAL_END(program_check, 0x700, 0x100)
EXC_VIRT_BEGIN(program_check, 0x4700, 0x100)
--
2.25.1
^ permalink raw reply related
* Re: [PATCH v12 14/14] powerpc/64s/radix: Enable huge vmalloc mappings
From: kernel test robot @ 2021-02-02 13:48 UTC (permalink / raw)
To: Nicholas Piggin, linux-mm, Andrew Morton
Cc: linux-arch, kbuild-all, linux-kernel, Nicholas Piggin,
Christoph Hellwig, Linux Memory Management List, Jonathan Cameron,
linuxppc-dev
In-Reply-To: <20210202110515.3575274-15-npiggin@gmail.com>
[-- Attachment #1: Type: text/plain, Size: 3280 bytes --]
Hi Nicholas,
I love your patch! Yet something to improve:
[auto build test ERROR on powerpc/next]
[also build test ERROR on arm64/for-next/core v5.11-rc6]
[cannot apply to hnaz-linux-mm/master next-20210125]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/0day-ci/linux/commits/Nicholas-Piggin/huge-vmalloc-mappings/20210202-190833
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-mpc834x_mds_defconfig (attached as .config)
compiler: powerpc-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/ba7c3aca8bdba641f1cc3cd3da5c19da2b5f721a
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review Nicholas-Piggin/huge-vmalloc-mappings/20210202-190833
git checkout ba7c3aca8bdba641f1cc3cd3da5c19da2b5f721a
# save the attached .config to linux build tree
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
In file included from arch/powerpc/include/asm/book3s/pgtable.h:8,
from arch/powerpc/include/asm/pgtable.h:18,
from include/linux/pgtable.h:6,
from arch/powerpc/include/asm/kup.h:50,
from arch/powerpc/include/asm/uaccess.h:9,
from include/linux/uaccess.h:11,
from arch/powerpc/kernel/module.c:13:
arch/powerpc/kernel/module.c: In function 'module_alloc':
>> arch/powerpc/include/asm/book3s/32/pgtable.h:189:32: error: 'high_memory' undeclared (first use in this function)
189 | #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
| ^~~~~~~~~~~
arch/powerpc/kernel/module.c:92:24: note: in expansion of macro 'VMALLOC_START'
92 | unsigned long start = VMALLOC_START;
| ^~~~~~~~~~~~~
arch/powerpc/include/asm/book3s/32/pgtable.h:189:32: note: each undeclared identifier is reported only once for each function it appears in
189 | #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
| ^~~~~~~~~~~
arch/powerpc/kernel/module.c:92:24: note: in expansion of macro 'VMALLOC_START'
92 | unsigned long start = VMALLOC_START;
| ^~~~~~~~~~~~~
vim +/high_memory +189 arch/powerpc/include/asm/book3s/32/pgtable.h
63b2bc619565ef Christophe Leroy 2019-02-21 188
3dfcb315d81e66 Aneesh Kumar K.V 2015-12-01 @189 #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)))
3d4247fcc938d0 Christophe Leroy 2020-01-14 190
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 15936 bytes --]
^ permalink raw reply
* Re: [PATCH 06/13] kallsyms: only build {, module_}kallsyms_on_each_symbol when required
From: Miroslav Benes @ 2021-02-02 14:03 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-7-hch@lst.de>
On Tue, 2 Feb 2021, Christoph Hellwig wrote:
> kallsyms_on_each_symbol and module_kallsyms_on_each_symbol are only used
> by the livepatching code, so don't build them if livepatching is not
> enabled.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
M
^ permalink raw reply
* Re: [PATCH 07/13] module: mark module_mutex static
From: Miroslav Benes @ 2021-02-02 14:04 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-8-hch@lst.de>
On Tue, 2 Feb 2021, Christoph Hellwig wrote:
> Except for two lockdep asserts module_mutex is only used in module.c.
> Remove the two asserts given that the functions they are in are not
> exported and just called from the module code, and mark module_mutex
> static.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
M
^ permalink raw reply
* Re: [PATCH 08/13] module: remove each_symbol_in_section
From: Miroslav Benes @ 2021-02-02 14:04 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-9-hch@lst.de>
On Tue, 2 Feb 2021, Christoph Hellwig wrote:
> each_symbol_in_section just contains a trivial loop over its arguments.
> Just open code the loop in the two callers.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
M
^ permalink raw reply
* Re: [PATCH 09/13] module: merge each_symbol_section into find_symbol
From: Miroslav Benes @ 2021-02-02 14:04 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-10-hch@lst.de>
On Tue, 2 Feb 2021, Christoph Hellwig wrote:
> each_symbol_section is only called by find_symbol, so merge the two
> functions.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
M
^ permalink raw reply
* Re: [PATCH 10/13] module: pass struct find_symbol_args to find_symbol
From: Miroslav Benes @ 2021-02-02 14:07 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-11-hch@lst.de>
> void *__symbol_get(const char *symbol)
> {
> - struct module *owner;
> - const struct kernel_symbol *sym;
> + struct find_symbol_arg fsa = {
> + .name = symbol,
> + .gplok = true,
> + .warn = true,
> + };
>
> preempt_disable();
> - sym = find_symbol(symbol, &owner, NULL, NULL, true, true);
> - if (sym && strong_try_module_get(owner))
> - sym = NULL;
> + if (!find_symbol(&fsa) || !strong_try_module_get(fsa.owner)) {
I think this should be in fact
if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) {
to get the logic right (note the missing !). We want to return NULL if
strong_try_module_get() does not succeed for a found symbol.
> + preempt_enable();
> + return NULL;
> + }
> preempt_enable();
> -
> - return sym ? (void *)kernel_symbol_value(sym) : NULL;
> + return (void *)kernel_symbol_value(fsa.sym);
> }
> EXPORT_SYMBOL_GPL(__symbol_get);
Miroslav
^ permalink raw reply
* Re: [PATCH 11/13] module: move struct symsearch to module.c
From: Miroslav Benes @ 2021-02-02 14:10 UTC (permalink / raw)
To: Christoph Hellwig
Cc: Petr Mladek, Jiri Kosina, Andrew Donnellan, linux-kbuild,
David Airlie, Masahiro Yamada, Josh Poimboeuf, Maarten Lankhorst,
linux-kernel, Maxime Ripard, live-patching, Michal Marek,
Joe Lawrence, dri-devel, Thomas Zimmermann, Jessica Yu,
Frederic Barrat, Daniel Vetter, linuxppc-dev
In-Reply-To: <20210202121334.1361503-12-hch@lst.de>
On Tue, 2 Feb 2021, Christoph Hellwig wrote:
> struct symsearch is only used inside of module.h, so move the definition
> out of module.h.
>
> Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
M
^ permalink raw reply
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