--- /dev/null
+From 87ffac18a977ffa70dfd4d347615eb4a880a115e Mon Sep 17 00:00:00 2001
+From: Sasha Levin <sashal@kernel.org>
+Date: Mon, 2 Dec 2019 07:57:29 +0000
+Subject: powerpc: Fix vDSO clock_getres()
+
+From: Vincenzo Frascino <vincenzo.frascino@arm.com>
+
+[ Upstream commit 552263456215ada7ee8700ce022d12b0cffe4802 ]
+
+clock_getres in the vDSO library has to preserve the same behaviour
+of posix_get_hrtimer_res().
+
+In particular, posix_get_hrtimer_res() does:
+ sec = 0;
+ ns = hrtimer_resolution;
+and hrtimer_resolution depends on the enablement of the high
+resolution timers that can happen either at compile or at run time.
+
+Fix the powerpc vdso implementation of clock_getres keeping a copy of
+hrtimer_resolution in vdso data and using that directly.
+
+Fixes: a7f290dad32e ("[PATCH] powerpc: Merge vdso's and add vdso support to 32 bits kernel")
+Cc: stable@vger.kernel.org
+Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
+Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
+Acked-by: Shuah Khan <skhan@linuxfoundation.org>
+[chleroy: changed CLOCK_REALTIME_RES to CLOCK_HRTIMER_RES]
+Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
+Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
+Link: https://lore.kernel.org/r/a55eca3a5e85233838c2349783bcb5164dae1d09.1575273217.git.christophe.leroy@c-s.fr
+Signed-off-by: Sasha Levin <sashal@kernel.org>
+---
+ arch/powerpc/include/asm/vdso_datapage.h | 2 ++
+ arch/powerpc/kernel/asm-offsets.c | 2 +-
+ arch/powerpc/kernel/time.c | 1 +
+ arch/powerpc/kernel/vdso32/gettimeofday.S | 7 +++++--
+ arch/powerpc/kernel/vdso64/gettimeofday.S | 7 +++++--
+ 5 files changed, 14 insertions(+), 5 deletions(-)
+
+diff --git a/arch/powerpc/include/asm/vdso_datapage.h b/arch/powerpc/include/asm/vdso_datapage.h
+index b73a8199f161c..5c2e1a28a9819 100644
+--- a/arch/powerpc/include/asm/vdso_datapage.h
++++ b/arch/powerpc/include/asm/vdso_datapage.h
+@@ -86,6 +86,7 @@ struct vdso_data {
+ __s32 wtom_clock_nsec;
+ struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
+ __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
++ __u32 hrtimer_res; /* hrtimer resolution */
+ __u32 syscall_map_64[SYSCALL_MAP_SIZE]; /* map of syscalls */
+ __u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+ };
+@@ -107,6 +108,7 @@ struct vdso_data {
+ __s32 wtom_clock_nsec;
+ struct timespec stamp_xtime; /* xtime as at tb_orig_stamp */
+ __u32 stamp_sec_fraction; /* fractional seconds of stamp_xtime */
++ __u32 hrtimer_res; /* hrtimer resolution */
+ __u32 syscall_map_32[SYSCALL_MAP_SIZE]; /* map of syscalls */
+ __u32 dcache_block_size; /* L1 d-cache block size */
+ __u32 icache_block_size; /* L1 i-cache block size */
+diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
+index de3c29c515034..ca46b572474ab 100644
+--- a/arch/powerpc/kernel/asm-offsets.c
++++ b/arch/powerpc/kernel/asm-offsets.c
+@@ -398,6 +398,7 @@ int main(void)
+ DEFINE(WTOM_CLOCK_NSEC, offsetof(struct vdso_data, wtom_clock_nsec));
+ DEFINE(STAMP_XTIME, offsetof(struct vdso_data, stamp_xtime));
+ DEFINE(STAMP_SEC_FRAC, offsetof(struct vdso_data, stamp_sec_fraction));
++ DEFINE(CLOCK_HRTIMER_RES, offsetof(vdso_data, hrtimer_res));
+ DEFINE(CFG_ICACHE_BLOCKSZ, offsetof(struct vdso_data, icache_block_size));
+ DEFINE(CFG_DCACHE_BLOCKSZ, offsetof(struct vdso_data, dcache_block_size));
+ DEFINE(CFG_ICACHE_LOGBLOCKSZ, offsetof(struct vdso_data, icache_log_block_size));
+@@ -426,7 +427,6 @@ int main(void)
+ DEFINE(CLOCK_REALTIME, CLOCK_REALTIME);
+ DEFINE(CLOCK_MONOTONIC, CLOCK_MONOTONIC);
+ DEFINE(NSEC_PER_SEC, NSEC_PER_SEC);
+- DEFINE(CLOCK_REALTIME_RES, MONOTONIC_RES_NSEC);
+
+ #ifdef CONFIG_BUG
+ DEFINE(BUG_ENTRY_SIZE, sizeof(struct bug_entry));
+diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
+index 9baba9576e998..2e9cae5f8d174 100644
+--- a/arch/powerpc/kernel/time.c
++++ b/arch/powerpc/kernel/time.c
+@@ -829,6 +829,7 @@ void update_vsyscall_old(struct timespec *wall_time, struct timespec *wtm,
+ vdso_data->wtom_clock_nsec = wtm->tv_nsec;
+ vdso_data->stamp_xtime = *wall_time;
+ vdso_data->stamp_sec_fraction = frac_sec;
++ vdso_data->hrtimer_res = hrtimer_resolution;
+ smp_wmb();
+ ++(vdso_data->tb_update_count);
+ }
+diff --git a/arch/powerpc/kernel/vdso32/gettimeofday.S b/arch/powerpc/kernel/vdso32/gettimeofday.S
+index 7b341b86216c2..9b24466570c84 100644
+--- a/arch/powerpc/kernel/vdso32/gettimeofday.S
++++ b/arch/powerpc/kernel/vdso32/gettimeofday.S
+@@ -160,12 +160,15 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
+ cror cr0*4+eq,cr0*4+eq,cr1*4+eq
+ bne cr0,99f
+
++ mflr r12
++ .cfi_register lr,r12
++ bl __get_datapage@local /* get data page */
++ lwz r5, CLOCK_HRTIMER_RES(r3)
++ mtlr r12
+ li r3,0
+ cmpli cr0,r4,0
+ crclr cr0*4+so
+ beqlr
+- lis r5,CLOCK_REALTIME_RES@h
+- ori r5,r5,CLOCK_REALTIME_RES@l
+ stw r3,TSPC32_TV_SEC(r4)
+ stw r5,TSPC32_TV_NSEC(r4)
+ blr
+diff --git a/arch/powerpc/kernel/vdso64/gettimeofday.S b/arch/powerpc/kernel/vdso64/gettimeofday.S
+index 09b2a49f6dd53..c973378e1f2bc 100644
+--- a/arch/powerpc/kernel/vdso64/gettimeofday.S
++++ b/arch/powerpc/kernel/vdso64/gettimeofday.S
+@@ -145,12 +145,15 @@ V_FUNCTION_BEGIN(__kernel_clock_getres)
+ cror cr0*4+eq,cr0*4+eq,cr1*4+eq
+ bne cr0,99f
+
++ mflr r12
++ .cfi_register lr,r12
++ bl V_LOCAL_FUNC(__get_datapage)
++ lwz r5, CLOCK_HRTIMER_RES(r3)
++ mtlr r12
+ li r3,0
+ cmpldi cr0,r4,0
+ crclr cr0*4+so
+ beqlr
+- lis r5,CLOCK_REALTIME_RES@h
+- ori r5,r5,CLOCK_REALTIME_RES@l
+ std r3,TSPC64_TV_SEC(r4)
+ std r5,TSPC64_TV_NSEC(r4)
+ blr
+--
+2.20.1
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
