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| author | Victor Kamensky <victor.kamensky@linaro.org> | 2014-09-04 07:07:33 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-09-12 18:38:59 +0200 |
| commit | d9981380b49b839ecaffbbe131908a342db68980 (patch) | |
| tree | bd39bf86b001180366029db52f5a3c7e9e5bd7e3 /arch/arm/lib/getuser.S | |
| parent | ARM: 8135/1: Fix in-correct barrier usage in SWP{B} emulation (diff) | |
| download | linux-d9981380b49b839ecaffbbe131908a342db68980.tar.xz linux-d9981380b49b839ecaffbbe131908a342db68980.zip | |
ARM: 8137/1: fix get_user BE behavior for target variable with size of 8 bytes
e38361d 'ARM: 8091/2: add get_user() support for 8 byte types' commit
broke V7 BE get_user call when target var size is 64 bit, but '*ptr' size
is 32 bit or smaller. e38361d changed type of __r2 from 'register
unsigned long' to 'register typeof(x) __r2 asm("r2")' i.e before the change
even when target variable size was 64 bit, __r2 was still 32 bit.
But after e38361d commit, for target var of 64 bit size, __r2 became 64
bit and now it should occupy 2 registers r2, and r3. The issue in BE case
that r3 register is least significant word of __r2 and r2 register is most
significant word of __r2. But __get_user_4 still copies result into r2 (most
significant word of __r2). Subsequent code copies from __r2 into x, but
for situation described it will pick up only garbage from r3 register.
Special __get_user_64t_(124) functions are introduced. They are similar to
corresponding __get_user_(124) function but result stored in r3 register
(lsw in case of 64 bit __r2 in BE image). Those function are used by
get_user macro in case of BE and target var size is 64bit.
Also changed __get_user_lo8 name into __get_user_32t_8 to get consistent
naming accross all cases.
Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib/getuser.S')
| -rw-r--r-- | arch/arm/lib/getuser.S | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/arch/arm/lib/getuser.S b/arch/arm/lib/getuser.S index 938600098b88..8ecfd15c3a02 100644 --- a/arch/arm/lib/getuser.S +++ b/arch/arm/lib/getuser.S @@ -80,7 +80,7 @@ ENTRY(__get_user_8) ENDPROC(__get_user_8) #ifdef __ARMEB__ -ENTRY(__get_user_lo8) +ENTRY(__get_user_32t_8) check_uaccess r0, 8, r1, r2, __get_user_bad #ifdef CONFIG_CPU_USE_DOMAINS add r0, r0, #4 @@ -90,7 +90,37 @@ ENTRY(__get_user_lo8) #endif mov r0, #0 ret lr -ENDPROC(__get_user_lo8) +ENDPROC(__get_user_32t_8) + +ENTRY(__get_user_64t_1) + check_uaccess r0, 1, r1, r2, __get_user_bad8 +8: TUSER(ldrb) r3, [r0] + mov r0, #0 + ret lr +ENDPROC(__get_user_64t_1) + +ENTRY(__get_user_64t_2) + check_uaccess r0, 2, r1, r2, __get_user_bad8 +#ifdef CONFIG_CPU_USE_DOMAINS +rb .req ip +9: ldrbt r3, [r0], #1 +10: ldrbt rb, [r0], #0 +#else +rb .req r0 +9: ldrb r3, [r0] +10: ldrb rb, [r0, #1] +#endif + orr r3, rb, r3, lsl #8 + mov r0, #0 + ret lr +ENDPROC(__get_user_64t_2) + +ENTRY(__get_user_64t_4) + check_uaccess r0, 4, r1, r2, __get_user_bad8 +11: TUSER(ldr) r3, [r0] + mov r0, #0 + ret lr +ENDPROC(__get_user_64t_4) #endif __get_user_bad8: @@ -111,5 +141,9 @@ ENDPROC(__get_user_bad8) .long 6b, __get_user_bad8 #ifdef __ARMEB__ .long 7b, __get_user_bad + .long 8b, __get_user_bad8 + .long 9b, __get_user_bad8 + .long 10b, __get_user_bad8 + .long 11b, __get_user_bad8 #endif .popsection |