* [PATCH AUTOSEL 5.6 279/606] csky: Fixup msa highest 3 bits mask [not found] <20200608231211.3363633-1-sashal@kernel.org> @ 2020-06-08 23:06 ` Sasha Levin 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 280/606] csky: Fixup perf callchain unwind Sasha Levin ` (2 subsequent siblings) 3 siblings, 0 replies; 4+ messages in thread From: Sasha Levin @ 2020-06-08 23:06 UTC (permalink / raw) To: linux-kernel, stable; +Cc: Liu Yibin, Guo Ren, Sasha Levin, linux-csky From: Liu Yibin <jiulong@linux.alibaba.com> [ Upstream commit 165f2d2858013253042809df082b8df7e34e86d7 ] Just as comment mentioned, the msa format: cr<30/31, 15> MSA register format: 31 - 29 | 28 - 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 BA Reserved SH WA B SO SEC C D V So we should shift 29 bits not 28 bits for mask Signed-off-by: Liu Yibin <jiulong@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/csky/abiv1/inc/abi/entry.h | 4 ++-- arch/csky/abiv2/inc/abi/entry.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/csky/abiv1/inc/abi/entry.h b/arch/csky/abiv1/inc/abi/entry.h index 5056ebb902d1..61d94ec7dd16 100644 --- a/arch/csky/abiv1/inc/abi/entry.h +++ b/arch/csky/abiv1/inc/abi/entry.h @@ -167,8 +167,8 @@ * BA Reserved C D V */ cprcr r6, cpcr30 - lsri r6, 28 - lsli r6, 28 + lsri r6, 29 + lsli r6, 29 addi r6, 0xe cpwcr r6, cpcr30 diff --git a/arch/csky/abiv2/inc/abi/entry.h b/arch/csky/abiv2/inc/abi/entry.h index 111973c6c713..9023828ede97 100644 --- a/arch/csky/abiv2/inc/abi/entry.h +++ b/arch/csky/abiv2/inc/abi/entry.h @@ -225,8 +225,8 @@ */ mfcr r6, cr<30, 15> /* Get MSA0 */ 2: - lsri r6, 28 - lsli r6, 28 + lsri r6, 29 + lsli r6, 29 addi r6, 0x1ce mtcr r6, cr<30, 15> /* Set MSA0 */ -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH AUTOSEL 5.6 280/606] csky: Fixup perf callchain unwind [not found] <20200608231211.3363633-1-sashal@kernel.org> 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 279/606] csky: Fixup msa highest 3 bits mask Sasha Levin @ 2020-06-08 23:06 ` Sasha Levin 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 281/606] csky: Fixup remove duplicate irq_disable Sasha Levin 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 286/606] csky: Fixup raw_copy_from_user() Sasha Levin 3 siblings, 0 replies; 4+ messages in thread From: Sasha Levin @ 2020-06-08 23:06 UTC (permalink / raw) To: linux-kernel, stable; +Cc: Mao Han, Guo Ren, Sasha Levin, linux-csky From: Mao Han <han_mao@linux.alibaba.com> [ Upstream commit 229a0ddee1108a3f82a873e6cbbe35c92c540444 ] [ 5221.974084] Unable to handle kernel paging request at virtual address 0xfffff000, pc: 0x8002c18e [ 5221.985929] Oops: 00000000 [ 5221.989488] [ 5221.989488] CURRENT PROCESS: [ 5221.989488] [ 5221.992877] COMM=callchain_test PID=11962 [ 5221.995213] TEXT=00008000-000087e0 DATA=00009f1c-0000a018 BSS=0000a018-0000b000 [ 5221.999037] USER-STACK=7fc18e20 KERNEL-STACK=be204680 [ 5221.999037] [ 5222.003292] PC: 0x8002c18e (perf_callchain_kernel+0x3e/0xd4) [ 5222.007957] LR: 0x8002c198 (perf_callchain_kernel+0x48/0xd4) [ 5222.074873] Call Trace: [ 5222.074873] [<800a248e>] get_perf_callchain+0x20a/0x29c [ 5222.074873] [<8009d964>] perf_callchain+0x64/0x80 [ 5222.074873] [<8009dc1c>] perf_prepare_sample+0x29c/0x4b8 [ 5222.074873] [<8009de6e>] perf_event_output_forward+0x36/0x98 [ 5222.074873] [<800497e0>] search_exception_tables+0x20/0x44 [ 5222.074873] [<8002cbb6>] do_page_fault+0x92/0x378 [ 5222.074873] [<80098608>] __perf_event_overflow+0x54/0xdc [ 5222.074873] [<80098778>] perf_swevent_hrtimer+0xe8/0x164 [ 5222.074873] [<8002ddd0>] update_mmu_cache+0x0/0xd8 [ 5222.074873] [<8002c014>] user_backtrace+0x58/0xc4 [ 5222.074873] [<8002c0b4>] perf_callchain_user+0x34/0xd0 [ 5222.074873] [<800a2442>] get_perf_callchain+0x1be/0x29c [ 5222.074873] [<8009d964>] perf_callchain+0x64/0x80 [ 5222.074873] [<8009d834>] perf_output_sample+0x78c/0x858 [ 5222.074873] [<8009dc1c>] perf_prepare_sample+0x29c/0x4b8 [ 5222.074873] [<8009de94>] perf_event_output_forward+0x5c/0x98 [ 5222.097846] [ 5222.097846] [<800a0300>] perf_event_exit_task+0x58/0x43c [ 5222.097846] [<8006c874>] hrtimer_interrupt+0x104/0x2ec [ 5222.097846] [<800a0300>] perf_event_exit_task+0x58/0x43c [ 5222.097846] [<80437bb6>] dw_apb_clockevent_irq+0x2a/0x4c [ 5222.097846] [<8006c770>] hrtimer_interrupt+0x0/0x2ec [ 5222.097846] [<8005f2e4>] __handle_irq_event_percpu+0xac/0x19c [ 5222.097846] [<80437bb6>] dw_apb_clockevent_irq+0x2a/0x4c [ 5222.097846] [<8005f408>] handle_irq_event_percpu+0x34/0x88 [ 5222.097846] [<8005f480>] handle_irq_event+0x24/0x64 [ 5222.097846] [<8006218c>] handle_level_irq+0x68/0xdc [ 5222.097846] [<8005ec76>] __handle_domain_irq+0x56/0xa8 [ 5222.097846] [<80450e90>] ck_irq_handler+0xac/0xe4 [ 5222.097846] [<80029012>] csky_do_IRQ+0x12/0x24 [ 5222.097846] [<8002a3a0>] csky_irq+0x70/0x80 [ 5222.097846] [<800ca612>] alloc_set_pte+0xd2/0x238 [ 5222.097846] [<8002ddd0>] update_mmu_cache+0x0/0xd8 [ 5222.097846] [<800a0340>] perf_event_exit_task+0x98/0x43c The original fp check doesn't base on the real kernal stack region. Invalid fp address may cause kernel panic. Signed-off-by: Mao Han <han_mao@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/csky/kernel/perf_callchain.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/csky/kernel/perf_callchain.c b/arch/csky/kernel/perf_callchain.c index e68ff375c8f8..ab55e98ee8f6 100644 --- a/arch/csky/kernel/perf_callchain.c +++ b/arch/csky/kernel/perf_callchain.c @@ -12,12 +12,17 @@ struct stackframe { static int unwind_frame_kernel(struct stackframe *frame) { - if (kstack_end((void *)frame->fp)) + unsigned long low = (unsigned long)task_stack_page(current); + unsigned long high = low + THREAD_SIZE; + + if (unlikely(frame->fp < low || frame->fp > high)) return -EPERM; - if (frame->fp & 0x3 || frame->fp < TASK_SIZE) + + if (kstack_end((void *)frame->fp) || frame->fp & 0x3) return -EPERM; *frame = *(struct stackframe *)frame->fp; + if (__kernel_text_address(frame->lr)) { int graph = 0; -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH AUTOSEL 5.6 281/606] csky: Fixup remove duplicate irq_disable [not found] <20200608231211.3363633-1-sashal@kernel.org> 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 279/606] csky: Fixup msa highest 3 bits mask Sasha Levin 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 280/606] csky: Fixup perf callchain unwind Sasha Levin @ 2020-06-08 23:06 ` Sasha Levin 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 286/606] csky: Fixup raw_copy_from_user() Sasha Levin 3 siblings, 0 replies; 4+ messages in thread From: Sasha Levin @ 2020-06-08 23:06 UTC (permalink / raw) To: linux-kernel, stable; +Cc: Liu Yibin, Guo Ren, Sasha Levin, linux-csky From: Liu Yibin <jiulong@linux.alibaba.com> [ Upstream commit 6633a5aa8eb6bda70eb3a9837efd28a67ccc6e0a ] Interrupt has been disabled in __schedule() with local_irq_disable() and enabled in finish_task_switch->finish_lock_switch() with local_irq_enabled(), So needn't to disable irq here. Signed-off-by: Liu Yibin <jiulong@linux.alibaba.com> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/csky/kernel/entry.S | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S index 007706328000..9718388448a4 100644 --- a/arch/csky/kernel/entry.S +++ b/arch/csky/kernel/entry.S @@ -318,8 +318,6 @@ ENTRY(__switch_to) mfcr a2, psr /* Save PSR value */ stw a2, (a3, THREAD_SR) /* Save PSR in task struct */ - bclri a2, 6 /* Disable interrupts */ - mtcr a2, psr SAVE_SWITCH_STACK -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH AUTOSEL 5.6 286/606] csky: Fixup raw_copy_from_user() [not found] <20200608231211.3363633-1-sashal@kernel.org> ` (2 preceding siblings ...) 2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 281/606] csky: Fixup remove duplicate irq_disable Sasha Levin @ 2020-06-08 23:06 ` Sasha Levin 3 siblings, 0 replies; 4+ messages in thread From: Sasha Levin @ 2020-06-08 23:06 UTC (permalink / raw) To: linux-kernel, stable; +Cc: Al Viro, Guo Ren, Sasha Levin, linux-csky From: Al Viro <viro@zeniv.linux.org.uk> [ Upstream commit 51bb38cb78363fdad1f89e87357b7bc73e39ba88 ] If raw_copy_from_user(to, from, N) returns K, callers expect the first N - K bytes starting at to to have been replaced with the contents of corresponding area starting at from and the last K bytes of destination *left* *unmodified*. What arch/sky/lib/usercopy.c is doing is broken - it can lead to e.g. data corruption on write(2). raw_copy_to_user() is inaccurate about return value, which is a bug, but consequences are less drastic than for raw_copy_from_user(). And just what are those access_ok() doing in there? I mean, look into linux/uaccess.h; that's where we do that check (as well as zero tail on failure in the callers that need zeroing). AFAICS, all of that shouldn't be hard to fix; something like a patch below might make a useful starting point. I would suggest moving these macros into usercopy.c (they are never used anywhere else) and possibly expanding them there; if you leave them alive, please at least rename __copy_user_zeroing(). Again, it must not zero anything on failed read. Said that, I'm not sure we won't be better off simply turning usercopy.c into usercopy.S - all that is left there is a couple of functions, each consisting only of inline asm. Guo Ren reply: Yes, raw_copy_from_user is wrong, it's no need zeroing code. unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n) { unsigned long res = n; might_fault(); if (likely(access_ok(from, n))) { kasan_check_write(to, n); res = raw_copy_from_user(to, from, n); } if (unlikely(res)) memset(to + (n - res), 0, res); return res; } EXPORT_SYMBOL(_copy_from_user); You are right and access_ok() should be removed. but, how about: do { ... "2: stw %3, (%1, 0) \n" \ + " subi %0, 4 \n" \ "9: stw %4, (%1, 4) \n" \ + " subi %0, 4 \n" \ "10: stw %5, (%1, 8) \n" \ + " subi %0, 4 \n" \ "11: stw %6, (%1, 12) \n" \ + " subi %0, 4 \n" \ " addi %2, 16 \n" \ " addi %1, 16 \n" \ Don't expand __ex_table AI Viro reply: Hey, I've no idea about the instruction scheduling on csky - if that doesn't slow the things down, all the better. It's just that copy_to_user() and friends are on fairly hot codepaths, and in quite a few situations they will dominate the speed of e.g. read(2). So I tried to keep the fast path unchanged. Up to the architecture maintainers, obviously. Which would be you... As for the fixups size increase (__ex_table size is unchanged)... You have each of those macros expanded exactly once. So the size is not a serious argument, IMO - useless complexity would be, if it is, in fact, useless; the size... not really, especially since those extra subi will at least offset it. Again, up to you - asm optimizations of (essentially) memcpy()-style loops are tricky and can depend upon the fairly subtle details of architecture. So even on something I know reasonably well I would resort to direct experiments if I can't pass the buck to architecture maintainers. It *is* worth optimizing - this is where read() from a file that is already in page cache spends most of the time, etc. Guo Ren reply: Thx, after fixup some typo “sub %0, 4”, apply the patch. TODO: - user copy/from codes are still need optimizing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Guo Ren <guoren@linux.alibaba.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- arch/csky/include/asm/uaccess.h | 49 +++++++++++++++++---------------- arch/csky/lib/usercopy.c | 8 ++---- 2 files changed, 28 insertions(+), 29 deletions(-) diff --git a/arch/csky/include/asm/uaccess.h b/arch/csky/include/asm/uaccess.h index eaa1c3403a42..60f8a4112588 100644 --- a/arch/csky/include/asm/uaccess.h +++ b/arch/csky/include/asm/uaccess.h @@ -254,7 +254,7 @@ do { \ extern int __get_user_bad(void); -#define __copy_user(to, from, n) \ +#define ___copy_to_user(to, from, n) \ do { \ int w0, w1, w2, w3; \ asm volatile( \ @@ -289,31 +289,34 @@ do { \ " subi %0, 4 \n" \ " br 3b \n" \ "5: cmpnei %0, 0 \n" /* 1B */ \ - " bf 8f \n" \ + " bf 13f \n" \ " ldb %3, (%2, 0) \n" \ "6: stb %3, (%1, 0) \n" \ " addi %2, 1 \n" \ " addi %1, 1 \n" \ " subi %0, 1 \n" \ " br 5b \n" \ - "7: br 8f \n" \ + "7: subi %0, 4 \n" \ + "8: subi %0, 4 \n" \ + "12: subi %0, 4 \n" \ + " br 13f \n" \ ".section __ex_table, \"a\" \n" \ ".align 2 \n" \ - ".long 2b, 7b \n" \ - ".long 9b, 7b \n" \ - ".long 10b, 7b \n" \ + ".long 2b, 13f \n" \ + ".long 4b, 13f \n" \ + ".long 6b, 13f \n" \ + ".long 9b, 12b \n" \ + ".long 10b, 8b \n" \ ".long 11b, 7b \n" \ - ".long 4b, 7b \n" \ - ".long 6b, 7b \n" \ ".previous \n" \ - "8: \n" \ + "13: \n" \ : "=r"(n), "=r"(to), "=r"(from), "=r"(w0), \ "=r"(w1), "=r"(w2), "=r"(w3) \ : "0"(n), "1"(to), "2"(from) \ : "memory"); \ } while (0) -#define __copy_user_zeroing(to, from, n) \ +#define ___copy_from_user(to, from, n) \ do { \ int tmp; \ int nsave; \ @@ -356,22 +359,22 @@ do { \ " addi %1, 1 \n" \ " subi %0, 1 \n" \ " br 5b \n" \ - "8: mov %3, %0 \n" \ - " movi %4, 0 \n" \ - "9: stb %4, (%1, 0) \n" \ - " addi %1, 1 \n" \ - " subi %3, 1 \n" \ - " cmpnei %3, 0 \n" \ - " bt 9b \n" \ - " br 7f \n" \ + "8: stw %3, (%1, 0) \n" \ + " subi %0, 4 \n" \ + " bf 7f \n" \ + "9: subi %0, 8 \n" \ + " bf 7f \n" \ + "13: stw %3, (%1, 8) \n" \ + " subi %0, 12 \n" \ + " bf 7f \n" \ ".section __ex_table, \"a\" \n" \ ".align 2 \n" \ - ".long 2b, 8b \n" \ + ".long 2b, 7f \n" \ + ".long 4b, 7f \n" \ + ".long 6b, 7f \n" \ ".long 10b, 8b \n" \ - ".long 11b, 8b \n" \ - ".long 12b, 8b \n" \ - ".long 4b, 8b \n" \ - ".long 6b, 8b \n" \ + ".long 11b, 9b \n" \ + ".long 12b,13b \n" \ ".previous \n" \ "7: \n" \ : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave), \ diff --git a/arch/csky/lib/usercopy.c b/arch/csky/lib/usercopy.c index 647a23986fb5..3c9bd645e643 100644 --- a/arch/csky/lib/usercopy.c +++ b/arch/csky/lib/usercopy.c @@ -7,10 +7,7 @@ unsigned long raw_copy_from_user(void *to, const void *from, unsigned long n) { - if (access_ok(from, n)) - __copy_user_zeroing(to, from, n); - else - memset(to, 0, n); + ___copy_from_user(to, from, n); return n; } EXPORT_SYMBOL(raw_copy_from_user); @@ -18,8 +15,7 @@ EXPORT_SYMBOL(raw_copy_from_user); unsigned long raw_copy_to_user(void *to, const void *from, unsigned long n) { - if (access_ok(to, n)) - __copy_user(to, from, n); + ___copy_to_user(to, from, n); return n; } EXPORT_SYMBOL(raw_copy_to_user); -- 2.25.1 ^ permalink raw reply related [flat|nested] 4+ messages in thread
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[not found] <20200608231211.3363633-1-sashal@kernel.org>
2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 279/606] csky: Fixup msa highest 3 bits mask Sasha Levin
2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 280/606] csky: Fixup perf callchain unwind Sasha Levin
2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 281/606] csky: Fixup remove duplicate irq_disable Sasha Levin
2020-06-08 23:06 ` [PATCH AUTOSEL 5.6 286/606] csky: Fixup raw_copy_from_user() Sasha Levin
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