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MAKE FILE ERROR #272

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sarfaraj118 opened this issue Nov 20, 2016 · 1 comment
Closed

MAKE FILE ERROR #272

sarfaraj118 opened this issue Nov 20, 2016 · 1 comment

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@sarfaraj118
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CC user/module.c
CC user/wiopkd.c
AR build/httpd_app.a
GEN ldscript_memspecific.ld
LD build/httpd.out
/home/sarfaraj/esp-open-sdk/xtensa-lx106-elf/lib/gcc/xtensa-lx106-elf/4.8.5/../../../../xtensa-lx106-elf/bin/ld:ldscript_memspecific.ld:1: warning: redeclaration of memory region irom0_0_seg' /home/sarfaraj/esp-open-sdk/xtensa-lx106-elf/lib/gcc/xtensa-lx106-elf/4.8.5/../../../../xtensa-lx106-elf/bin/ld: build/httpd.out section.text' will not fit in region `iram1_0_seg'
collect2: error: ld returned 1 exit status
Makefile.combined:22: recipe for target 'build/httpd.out' failed
make: *** [build/httpd.out] Error 1

how can i remove this error i am installed latest toolchain and SDK .could you tell me how remove warning treat as error ?

@turl
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turl commented Nov 20, 2016

That doesn't look like a sunxi kernel build to me. Please report your issue to the correct project.

@turl turl closed this as completed Nov 20, 2016
wens pushed a commit that referenced this issue Jun 8, 2017
split __bpf_prog_run() interpreter into stack allocation and execution parts.
The code section shrinks which helps interpreter performance in some cases.
   text	   data	    bss	    dec	    hex	filename
  26350	  10328	    624	  37302	   91b6	kernel/bpf/core.o.before
  25777	  10328	    624	  36729	   8f79	kernel/bpf/core.o.after

Very short programs got slower (due to extra function call):
Before:
test_bpf: #89 ALU64_ADD_K: 1 + 2 = 3 jited:0 7 PASS
test_bpf: #90 ALU64_ADD_K: 3 + 0 = 3 jited:0 8 PASS
test_bpf: #91 ALU64_ADD_K: 1 + 2147483646 = 2147483647 jited:0 7 PASS
test_bpf: #92 ALU64_ADD_K: 4294967294 + 2 = 4294967296 jited:0 11 PASS
test_bpf: #93 ALU64_ADD_K: 2147483646 + -2147483647 = -1 jited:0 7 PASS
After:
test_bpf: #89 ALU64_ADD_K: 1 + 2 = 3 jited:0 11 PASS
test_bpf: #90 ALU64_ADD_K: 3 + 0 = 3 jited:0 11 PASS
test_bpf: #91 ALU64_ADD_K: 1 + 2147483646 = 2147483647 jited:0 11 PASS
test_bpf: #92 ALU64_ADD_K: 4294967294 + 2 = 4294967296 jited:0 14 PASS
test_bpf: #93 ALU64_ADD_K: 2147483646 + -2147483647 = -1 jited:0 10 PASS

Longer programs got faster:
Before:
test_bpf: #266 BPF_MAXINSNS: Ctx heavy transformations jited:0 20286 20513 PASS
test_bpf: #267 BPF_MAXINSNS: Call heavy transformations jited:0 31853 31768 PASS
test_bpf: #268 BPF_MAXINSNS: Jump heavy test jited:0 9815 PASS
test_bpf: #269 BPF_MAXINSNS: Very long jump backwards jited:0 6 PASS
test_bpf: #270 BPF_MAXINSNS: Edge hopping nuthouse jited:0 13959 PASS
test_bpf: #271 BPF_MAXINSNS: Jump, gap, jump, ... jited:0 210 PASS
test_bpf: #272 BPF_MAXINSNS: ld_abs+get_processor_id jited:0 21724 PASS
test_bpf: #273 BPF_MAXINSNS: ld_abs+vlan_push/pop jited:0 19118 PASS
After:
test_bpf: #266 BPF_MAXINSNS: Ctx heavy transformations jited:0 19008 18827 PASS
test_bpf: #267 BPF_MAXINSNS: Call heavy transformations jited:0 29238 28450 PASS
test_bpf: #268 BPF_MAXINSNS: Jump heavy test jited:0 9485 PASS
test_bpf: #269 BPF_MAXINSNS: Very long jump backwards jited:0 12 PASS
test_bpf: #270 BPF_MAXINSNS: Edge hopping nuthouse jited:0 13257 PASS
test_bpf: #271 BPF_MAXINSNS: Jump, gap, jump, ... jited:0 213 PASS
test_bpf: #272 BPF_MAXINSNS: ld_abs+get_processor_id jited:0 19389 PASS
test_bpf: #273 BPF_MAXINSNS: ld_abs+vlan_push/pop jited:0 19583 PASS

For real world production programs the difference is noise.

This patch is first step towards reducing interpreter stack consumption.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
amery pushed a commit that referenced this issue Feb 24, 2018
I recently noticed a crash on arm64 when feeding a bogus index
into BPF tail call helper. The crash would not occur when the
interpreter is used, but only in case of JIT. Output looks as
follows:

  [  347.007486] Unable to handle kernel paging request at virtual address fffb850e96492510
  [...]
  [  347.043065] [fffb850e96492510] address between user and kernel address ranges
  [  347.050205] Internal error: Oops: 96000004 [#1] SMP
  [...]
  [  347.190829] x13: 0000000000000000 x12: 0000000000000000
  [  347.196128] x11: fffc047ebe782800 x10: ffff808fd7d0fd10
  [  347.201427] x9 : 0000000000000000 x8 : 0000000000000000
  [  347.206726] x7 : 0000000000000000 x6 : 001c991738000000
  [  347.212025] x5 : 0000000000000018 x4 : 000000000000ba5a
  [  347.217325] x3 : 00000000000329c4 x2 : ffff808fd7cf0500
  [  347.222625] x1 : ffff808fd7d0fc00 x0 : ffff808fd7cf0500
  [  347.227926] Process test_verifier (pid: 4548, stack limit = 0x000000007467fa61)
  [  347.235221] Call trace:
  [  347.237656]  0xffff000002f3a4fc
  [  347.240784]  bpf_test_run+0x78/0xf8
  [  347.244260]  bpf_prog_test_run_skb+0x148/0x230
  [  347.248694]  SyS_bpf+0x77c/0x1110
  [  347.251999]  el0_svc_naked+0x30/0x34
  [  347.255564] Code: 9100075a d280220a 8b0a002a d37df04b (f86b694b)
  [...]

In this case the index used in BPF r3 is the same as in r1
at the time of the call, meaning we fed a pointer as index;
here, it had the value 0xffff808fd7cf0500 which sits in x2.

While I found tail calls to be working in general (also for
hitting the error cases), I noticed the following in the code
emission:

  # bpftool p d j i 988
  [...]
  38:   ldr     w10, [x1,x10]
  3c:   cmp     w2, w10
  40:   b.ge    0x000000000000007c              <-- signed cmp
  44:   mov     x10, #0x20                      // #32
  48:   cmp     x26, x10
  4c:   b.gt    0x000000000000007c
  50:   add     x26, x26, #0x1
  54:   mov     x10, #0x110                     // #272
  58:   add     x10, x1, x10
  5c:   lsl     x11, x2, #3
  60:   ldr     x11, [x10,x11]                  <-- faulting insn (f86b694b)
  64:   cbz     x11, 0x000000000000007c
  [...]

Meaning, the tests passed because commit ddb5599 ("arm64:
bpf: implement bpf_tail_call() helper") was using signed compares
instead of unsigned which as a result had the test wrongly passing.

Change this but also the tail call count test both into unsigned
and cap the index as u32. Latter we did as well in 90caccd
("bpf: fix bpf_tail_call() x64 JIT") and is needed in addition here,
too. Tested on HiSilicon Hi1616.

Result after patch:

  # bpftool p d j i 268
  [...]
  38:	ldr	w10, [x1,x10]
  3c:	add	w2, w2, #0x0
  40:	cmp	w2, w10
  44:	b.cs	0x0000000000000080
  48:	mov	x10, #0x20                  	// #32
  4c:	cmp	x26, x10
  50:	b.hi	0x0000000000000080
  54:	add	x26, x26, #0x1
  58:	mov	x10, #0x110                 	// #272
  5c:	add	x10, x1, x10
  60:	lsl	x11, x2, #3
  64:	ldr	x11, [x10,x11]
  68:	cbz	x11, 0x0000000000000080
  [...]

Fixes: ddb5599 ("arm64: bpf: implement bpf_tail_call() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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