kernel.git/arch/powerpc/kernel/vdso.c, branch linux-4.14.y

powerpc/vdso: Fix vdso cpu truncation

2020-08-21T07:48:09Z

[ Upstream commit a9f675f950a07d5c1dbcbb97aabac56f5ed085e3 ] The code in vdso_cpu_init that exposes the cpu and numa node to userspace via SPRG_VDSO incorrctly masks the cpu to 12 bits. This means that any kernel running on a box with more than 4096 threads (NR_CPUS advertises a limit of of 8192 cpus) would expose userspace to two cpu contexts running at the same time with the same cpu number. Note: I'm not aware of any distro shipping a kernel with support for more than 4096 threads today, nor of any system image that currently exceeds 4096 threads. Found via code browsing. Fixes: 18ad51dd342a7eb09dbcd059d0b451b616d4dafc ("powerpc: Add VDSO version of getcpu") Signed-off-by: Milton Miller Signed-off-by: Anton Blanchard Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200715233704.1352257-1-anton@ozlabs.org Signed-off-by: Sasha Levin

powerpc/64: Clean up ppc64_caches using a struct per cache

2017-02-06T08:46:04Z

We have two set of identical struct members for the I and D sides and mostly identical bunches of code to parse the device-tree to populate them. Instead make a ppc_cache_info structure with one copy for I and one for D Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc/64: Fix naming of cache block vs. cache line

2017-02-06T08:46:04Z

In a number of places we called "cache line size" what is actually the cache block size, which in the powerpc architecture, means the effective size to use with cache management instructions (it can be different from the actual cache line size). We fix the naming across the board and properly retrieve both pieces of information when available in the device-tree. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman

powerpc/vdso: Add missing include file

2016-08-09T06:52:00Z

Some powerpc builds fail with the following buld error. In file included from ./arch/powerpc/include/asm/mmu_context.h:11:0, from arch/powerpc/kernel/vdso.c:28: arch/powerpc/include/asm/cputhreads.h: In function 'get_tensr': arch/powerpc/include/asm/cputhreads.h:101:2: error: implicit declaration of function 'cpu_has_feature' Fixes: b92a226e5284 ("powerpc: Move cpu_has_feature() to a separate file") Signed-off-by: Guenter Roeck Signed-off-by: Michael Ellerman

vdso: make arch_setup_additional_pages wait for mmap_sem for write killable

2016-05-24T00:04:14Z

most architectures are relying on mmap_sem for write in their arch_setup_additional_pages. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Michal Hocko Acked-by: Andy Lutomirski [x86 vdso] Acked-by: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

powerpc: Standardise on NR_syscalls rather than __NR_syscalls.

2015-11-26T11:11:17Z

Most architectures use NR_syscalls as the #define for the number of syscalls. We use __NR_syscalls, and then define NR_syscalls as __NR_syscalls. __NR_syscalls is not used outside arch code, whereas NR_syscalls is. So as NR_syscalls must be defined and __NR_syscalls does not, replace __NR_syscalls with NR_syscalls. Signed-off-by: Rashmica Gupta Signed-off-by: Michael Ellerman

powerpc/vdso: Disable building the 32-bit VDSO on little endian

2015-05-11T10:01:02Z

The only little endian configuration we support is ppc64le. As such if we're building little endian we don't need a 32-bit VDSO, because there is no 32-bit userspace. This patch is a fairly ugly mess of #ifdefs, but is the minimal logic required to disable the 32-bit VDSO. We can hopefully clean up the result in future with some further refactoring. Signed-off-by: Michael Ellerman

powerpc/vdso: Combine start/size variables

2015-05-11T10:00:32Z

In vdso_fixup_features() we have start64/start32 and size64/size32, but they have the same types, ie. void * and unsigned long. They're only used to save the return value from find_sectionXX() for the subsequent call to do_feature_fixups(), so there's no overlap in their usage either. So we can just consolidate them into start/size and avoid the duplication. Signed-off-by: Michael Ellerman

powerpc/vdso: Remove unused debug code

2015-05-11T10:00:32Z

It's in the git history if we ever need it back. Signed-off-by: Michael Ellerman

powerpc: Remove superfluous bootmem includes

2014-11-09T22:59:26Z

Lots of places included bootmem.h even when not using bootmem. Signed-off-by: Anton Blanchard Tested-by: Emil Medve Signed-off-by: Michael Ellerman