Messages in this thread | | | Date | Wed, 13 Apr 2022 15:30:38 +0800 | Subject | Re: [RFC PATCH -next V3 4/6] arm64: add copy_{to, from}_user to machine check safe | From | Tong Tiangen <> |
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在 2022/4/13 1:08, Robin Murphy 写道: > On 12/04/2022 8:25 am, Tong Tiangen wrote: > [...] >> diff --git a/arch/arm64/include/asm/asm-uaccess.h >> b/arch/arm64/include/asm/asm-uaccess.h >> index 0557af834e03..bb17f0829042 100644 >> --- a/arch/arm64/include/asm/asm-uaccess.h >> +++ b/arch/arm64/include/asm/asm-uaccess.h >> @@ -92,4 +92,20 @@ alternative_else_nop_endif >> _asm_extable 8888b,\l; >> .endm >> + >> + .macro user_ldp_mc l, reg1, reg2, addr, post_inc >> +8888: ldtr \reg1, [\addr]; >> +8889: ldtr \reg2, [\addr, #8]; >> + add \addr, \addr, \post_inc; >> + >> + _asm_extable_uaccess_mc 8888b, \l; >> + _asm_extable_uaccess_mc 8889b, \l; >> + .endm > > You're replacing the only user of this, so please just > s/_asm_extable/_asm_extable_uaccess_mc/ in the existing macro and save > the rest of the churn. > > Furthermore, how come you're not similarly updating user_stp, given that > you *are* updating the other stores in copy_to_user?
I think all load/store instructions should be handled.
Generally speaking, the load operation will receive a sea when consuming a hardware memory error, and the store operation will not receive a sea when consuming a hardware error. Depends on chip behavior.
So add store class instructions to processed is no harm.
If there is any problem with my understanding, correct me.
Thanks, Tong.
> >> + >> + .macro user_ldst_mc l, inst, reg, addr, post_inc >> +8888: \inst \reg, [\addr]; >> + add \addr, \addr, \post_inc; >> + >> + _asm_extable_uaccess_mc 8888b, \l; >> + .endm > [...]
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