[PATCH] powerpc: use ARRAY_SIZE instead of division operation

This eliminates the following coccicheck warning: ./arch/powerpc/boot/mktree.c:130:31-32: WARNING: Use ARRAY_SIZE Reported-by: Abaci Robot Signed-off-by: Yang Li --- arch/powerpc/boot/mktree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/boot/mktree.c b/arch/

[PATCH] powerpc/sstep: Use bitwise instead of arithmetic operator for flags

Fix the following coccinelle warnings: ./arch/powerpc/lib/sstep.c:1090:20-21: WARNING: sum of probable bitmasks, consider | ./arch/powerpc/lib/sstep.c:1115:20-21: WARNING: sum of probable bitmasks, consider | ./arch/powerpc/lib/sstep.c:1134:20-21: WARNING: sum of probable bitmasks, consider | Repo

Re: [PATCH v2] powerpc/kexec_file: Restore FDT size estimation for kdump kernel

On 20/02/21 6:22 am, Thiago Jung Bauermann wrote: Commit 2377c92e37fe ("powerpc/kexec_file: fix FDT size estimation for kdump kernel") fixed how elf64_load() estimates the FDT size needed by the crashdump kernel. At the same time, commit 130b2d59cec0 ("powerpc: Use common of_kexec_alloc_and_s

[PATCH v6 01/10] powerpc/uaccess: Add unsafe_copy_from_user

Just wrap __copy_tofrom_user() for the usual 'unsafe' pattern which accepts a label to goto on error. Signed-off-by: Christopher M. Riedl Reviewed-by: Daniel Axtens --- arch/powerpc/include/asm/uaccess.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/include/asm/uaccess.h

[PATCH v6 04/10] powerpc: Reference parameter in MSR_TM_ACTIVE() macro

Unlike the other MSR_TM_* macros, MSR_TM_ACTIVE does not reference or use its parameter unless CONFIG_PPC_TRANSACTIONAL_MEM is defined. This causes an 'unused variable' compile warning unless the variable is also guarded with CONFIG_PPC_TRANSACTIONAL_MEM. Reference but do nothing with the argument

[PATCH v6 03/10] powerpc/signal64: Remove non-inline calls from setup_sigcontext()

The majority of setup_sigcontext() can be refactored to execute in an "unsafe" context assuming an open uaccess window except for some non-inline function calls. Move these out into a separate prepare_setup_sigcontext() function which must be called first and before opening up a uaccess window. Non

[PATCH v6 02/10] powerpc/signal: Add unsafe_copy_{vsx, fpr}_from_user()

Reuse the "safe" implementation from signal.c but call unsafe_get_user() directly in a loop to avoid the intermediate copy into a local buffer. Signed-off-by: Christopher M. Riedl Reviewed-by: Daniel Axtens --- arch/powerpc/kernel/signal.h | 26 ++ 1 file changed, 26 ins

[PATCH v6 07/10] powerpc/signal64: Replace restore_sigcontext() w/ unsafe_restore_sigcontext()

Previously restore_sigcontext() performed a costly KUAP switch on every uaccess operation. These repeated uaccess switches cause a significant drop in signal handling performance. Rewrite restore_sigcontext() to assume that a userspace read access window is open by replacing all uaccess functions

[PATCH v6 09/10] powerpc/signal64: Rewrite rt_sigreturn() to minimise uaccess switches

From: Daniel Axtens Add uaccess blocks and use the 'unsafe' versions of functions doing user access where possible to reduce the number of times uaccess has to be opened/closed. Signed-off-by: Daniel Axtens Co-developed-by: Christopher M. Riedl Signed-off-by: Christopher M. Riedl --- arch/po

[PATCH v6 10/10] powerpc/signal: Use __get_user() to copy sigset_t

Usually sigset_t is exactly 8B which is a "trivial" size and does not warrant using __copy_from_user(). Use __get_user() directly in anticipation of future work to remove the trivial size optimizations from __copy_from_user(). The ppc32 implementation of get_sigset_t() previously called copy_from_

[PATCH v6 08/10] powerpc/signal64: Rewrite handle_rt_signal64() to minimise uaccess switches

From: Daniel Axtens Add uaccess blocks and use the 'unsafe' versions of functions doing user access where possible to reduce the number of times uaccess has to be opened/closed. There is no 'unsafe' version of copy_siginfo_to_user, so move it slightly to allow for a "longer" uaccess block. Sign

[PATCH v6 00/10] Improve signal performance on PPC64 with KUAP

As reported by Anton, there is a large penalty to signal handling performance on radix systems using KUAP. The signal handling code performs many user access operations, each of which needs to switch the KUAP permissions bit to open and then close user access. This involves a costly 'mtspr' operati

[PATCH v6 05/10] powerpc/signal64: Remove TM ifdefery in middle of if/else block

Both rt_sigreturn() and handle_rt_signal_64() contain TM-related ifdefs which break-up an if/else block. Provide stubs for the ifdef-guarded TM functions and remove the need for an ifdef in rt_sigreturn(). Rework the remaining TM ifdef in handle_rt_signal64() similar to commit f1cf4f93de2f ("power

[PATCH v6 06/10] powerpc/signal64: Replace setup_sigcontext() w/ unsafe_setup_sigcontext()

Previously setup_sigcontext() performed a costly KUAP switch on every uaccess operation. These repeated uaccess switches cause a significant drop in signal handling performance. Rewrite setup_sigcontext() to assume that a userspace write access window is open by replacing all uaccess functions wit