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[PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()

Christophe Leroy posted 9 patches 1 year, 5 months ago
There is a newer version of this series
[PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()
Posted by Christophe Leroy 1 year, 5 months ago 
_vdso_data is specific to x86 and __arch_get_k_vdso_data() is provided
so that all architectures can provide the requested pointer.

Do the same with _vdso_rng_data, provide __arch_get_k_vdso_rng_data()
and don't use x86 _vdso_rng_data directly.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
 arch/x86/include/asm/vdso/vsyscall.h | 7 +++++++
 drivers/char/random.c                | 5 +++--
 include/asm-generic/vdso/vsyscall.h  | 7 +++++++
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/vdso/vsyscall.h b/arch/x86/include/asm/vdso/vsyscall.h
index 972415a8be31..92b85189b8fe 100644
--- a/arch/x86/include/asm/vdso/vsyscall.h
+++ b/arch/x86/include/asm/vdso/vsyscall.h
@@ -22,6 +22,13 @@ struct vdso_data *__x86_get_k_vdso_data(void)
 }
 #define __arch_get_k_vdso_data __x86_get_k_vdso_data
 
+static __always_inline
+struct vdso_rng_data *__x86_get_k_vdso_rng_data(void)
+{
+	return &_vdso_rng_data;
+}
+#define __arch_get_k_vdso_rng_data __x86_get_k_vdso_rng_data
+
 /* The asm-generic header needs to be included after the definitions above */
 #include <asm-generic/vdso/vsyscall.h>
 
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 87fe61295ea1..77968309e2c2 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -59,6 +59,7 @@
 #ifdef CONFIG_VDSO_GETRANDOM
 #include <vdso/getrandom.h>
 #include <vdso/datapage.h>
+#include <vdso/vsyscall.h>
 #endif
 #include <asm/archrandom.h>
 #include <asm/processor.h>
@@ -282,7 +283,7 @@ static void crng_reseed(struct work_struct *work)
 	 * is ordered with the write above to base_crng.generation. Pairs with
 	 * the smp_rmb() before the syscall in the vDSO code.
 	 */
-	smp_store_release(&_vdso_rng_data.generation, next_gen + 1);
+	smp_store_release(&__arch_get_k_vdso_rng_data()->generation, next_gen + 1);
 #endif
 	if (!static_branch_likely(&crng_is_ready))
 		crng_init = CRNG_READY;
@@ -735,7 +736,7 @@ static void __cold _credit_init_bits(size_t bits)
 			queue_work(system_unbound_wq, &set_ready);
 		atomic_notifier_call_chain(&random_ready_notifier, 0, NULL);
 #ifdef CONFIG_VDSO_GETRANDOM
-		WRITE_ONCE(_vdso_rng_data.is_ready, true);
+		WRITE_ONCE(__arch_get_k_vdso_rng_data()->is_ready, true);
 #endif
 		wake_up_interruptible(&crng_init_wait);
 		kill_fasync(&fasync, SIGIO, POLL_IN);
diff --git a/include/asm-generic/vdso/vsyscall.h b/include/asm-generic/vdso/vsyscall.h
index c835607f78ae..d44a828e34a4 100644
--- a/include/asm-generic/vdso/vsyscall.h
+++ b/include/asm-generic/vdso/vsyscall.h
@@ -11,6 +11,13 @@ static __always_inline struct vdso_data *__arch_get_k_vdso_data(void)
 }
 #endif /* __arch_get_k_vdso_data */
 
+#ifndef __arch_get_k_vdso_rng_data
+static __always_inline struct vdso_rng_data *__arch_get_k_vdso_rng_data(void)
+{
+	return NULL;
+}
+#endif /* __arch_get_k_vdso_rng_data */
+
 #ifndef __arch_update_vsyscall
 static __always_inline void __arch_update_vsyscall(struct vdso_data *vdata,
 						   struct timekeeper *tk)
-- 
2.44.0
Re: [PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()
Posted by kernel test robot 1 year, 5 months ago 
Hi Christophe,

kernel test robot noticed the following build errors:

[auto build test ERROR on powerpc/next]
[also build test ERROR on powerpc/fixes crng-random/master shuah-kselftest/next shuah-kselftest/fixes linus/master v6.11-rc3 next-20240816]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Christophe-Leroy/powerpc-vdso-Don-t-discard-rela-sections/20240816-223917
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
patch link:    https://lore.kernel.org/r/a7bdbbb14d8635c1e33ada7982cf2cd1a8321e5c.1723817900.git.christophe.leroy%40csgroup.eu
patch subject: [PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()
config: x86_64-buildonly-randconfig-002-20240817 (https://download.01.org/0day-ci/archive/20240817/202408172143.g3Qxmakr-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240817/202408172143.g3Qxmakr-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202408172143.g3Qxmakr-lkp@intel.com/

All errors (new ones prefixed by >>):

>> ld: drivers/char/random.o:(.vvar__vdso_rng_data+0x0): multiple definition of `_vdso_rng_data'; kernel/time/vsyscall.o:(.vvar__vdso_rng_data+0x0): first defined here
>> ld: drivers/char/random.o:(.vvar__vdso_data+0x0): multiple definition of `_vdso_data'; kernel/time/vsyscall.o:(.vvar__vdso_data+0x0): first defined here

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Re: [PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()
Posted by kernel test robot 1 year, 5 months ago 
Hi Christophe,

kernel test robot noticed the following build errors:

[auto build test ERROR on powerpc/next]
[also build test ERROR on powerpc/fixes crng-random/master shuah-kselftest/next shuah-kselftest/fixes linus/master v6.11-rc3 next-20240816]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Christophe-Leroy/powerpc-vdso-Don-t-discard-rela-sections/20240816-223917
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
patch link:    https://lore.kernel.org/r/a7bdbbb14d8635c1e33ada7982cf2cd1a8321e5c.1723817900.git.christophe.leroy%40csgroup.eu
patch subject: [PATCH 3/9] vdso: Add __arch_get_k_vdso_rng_data()
config: x86_64-randconfig-003-20240817 (https://download.01.org/0day-ci/archive/20240817/202408172056.OAokF1z5-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240817/202408172056.OAokF1z5-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202408172056.OAokF1z5-lkp@intel.com/

All errors (new ones prefixed by >>):

>> ld: drivers/char/random.o:arch/x86/include/asm/vdso/vsyscall.h:13: multiple definition of `_vdso_rng_data'; kernel/time/vsyscall.o:arch/x86/include/asm/vdso/vsyscall.h:13: first defined here
>> ld: drivers/char/random.o:arch/x86/include/asm/vdso/vsyscall.h:12: multiple definition of `_vdso_data'; kernel/time/vsyscall.o:arch/x86/include/asm/vdso/vsyscall.h:12: first defined here

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

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