Thanks for the update, Phillips.
Yes, please add me, Stephen and Ana (CCed) to Phabricator reviews.
Zhaoshi
From: Mitch Phillips <mitchp at google.com>
Sent: Tuesday, July 14, 2020 19:10
To: Zhaoshi Zheng <zhaoshiz at quicinc.com>
Cc: llvm-dev at lists.llvm.org; Stephen Long <steplong at quicinc.com>
Subject: [EXT] Re: [llvm-dev] [MTE] Tagging Globals
Hi Zhaoshi,
Currently there's no global tagging instrumentation for MTE. We have a good
idea about the implementation's design - but no patches are ready to be
shared at this stage.
If you'd like - I'd be more than happy to CC yourself and Stephen on any
Phabricator reviews :).
On Tue, Jul 14, 2020 at 5:04 PM Zhaoshi Zheng via llvm-dev <llvm-dev at
lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote:
Hello,
We’re evaluating memory tagging (MTE) on some internal workloads.
We noticed that stack variables are tagged by an instrumentation pass and heap
objects are handled by the allocator (Scudo).
How about global variables? We tried a simple case using -march=armv8a+memtag
-fsanitize=memtag, but found no tagging:
Are we missing anything or tagging globals is still in progress?
int global_array[16];
int main(int argc, char **argv) {
global_array[1] = 0;
return global_array[argc + 16]; // BOOM
}
clang++ -O1 --target=aarch64-linux -march=armv8.5a+memtag -fsanitize=memtag
test.cpp -S -o test.s
main: // @main
.Lmain$local:
// %bb.0: // %entry
adrp x8, global_array
add x8, x8, :lo12:global_array
str wzr, [x8, #4]
add x8, x8, w0, sxtw #2
ldr w0, [x8, #64]
ret
.Lfunc_end0:
.size main, .Lfunc_end0-main
_______________________________________________
LLVM Developers mailing list
llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
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Mitch,
I forgot to ask: do you have any timeline on sharing it through Phabricator?
Thanks,
Zhaoshi
From: llvm-dev <llvm-dev-bounces at lists.llvm.org> On Behalf Of Zhaoshi
Zheng via llvm-dev
Sent: Tuesday, July 14, 2020 21:34
To: Mitch Phillips <mitchp at google.com>
Cc: llvm-dev at lists.llvm.org; Stephen Long <steplong at quicinc.com>
Subject: [EXT] Re: [llvm-dev] [MTE] Tagging Globals
Thanks for the update, Phillips.
Yes, please add me, Stephen and Ana (CCed) to Phabricator reviews.
Zhaoshi
From: Mitch Phillips <mitchp at google.com<mailto:mitchp at
google.com>>
Sent: Tuesday, July 14, 2020 19:10
To: Zhaoshi Zheng <zhaoshiz at quicinc.com<mailto:zhaoshiz at
quicinc.com>>
Cc: llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>; Stephen
Long <steplong at quicinc.com<mailto:steplong at quicinc.com>>
Subject: [EXT] Re: [llvm-dev] [MTE] Tagging Globals
Hi Zhaoshi,
Currently there's no global tagging instrumentation for MTE. We have a good
idea about the implementation's design - but no patches are ready to be
shared at this stage.
If you'd like - I'd be more than happy to CC yourself and Stephen on any
Phabricator reviews :).
On Tue, Jul 14, 2020 at 5:04 PM Zhaoshi Zheng via llvm-dev <llvm-dev at
lists.llvm.org<mailto:llvm-dev at lists.llvm.org>> wrote:
Hello,
We’re evaluating memory tagging (MTE) on some internal workloads.
We noticed that stack variables are tagged by an instrumentation pass and heap
objects are handled by the allocator (Scudo).
How about global variables? We tried a simple case using -march=armv8a+memtag
-fsanitize=memtag, but found no tagging:
Are we missing anything or tagging globals is still in progress?
int global_array[16];
int main(int argc, char **argv) {
global_array[1] = 0;
return global_array[argc + 16]; // BOOM
}
clang++ -O1 --target=aarch64-linux -march=armv8.5a+memtag -fsanitize=memtag
test.cpp -S -o test.s
main: // @main
.Lmain$local:
// %bb.0: // %entry
adrp x8, global_array
add x8, x8, :lo12:global_array
str wzr, [x8, #4]
add x8, x8, w0, sxtw #2
ldr w0, [x8, #64]
ret
.Lfunc_end0:
.size main, .Lfunc_end0-main
_______________________________________________
LLVM Developers mailing list
llvm-dev at lists.llvm.org<mailto:llvm-dev at lists.llvm.org>
https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
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Not at this stage -- no. On Wed, Jul 15, 2020 at 3:23 PM Zhaoshi Zheng <zhaoshiz at quicinc.com> wrote:> Mitch, > > > > I forgot to ask: do you have any timeline on sharing it through > Phabricator? > > > > Thanks, > > Zhaoshi > > > > *From:* llvm-dev <llvm-dev-bounces at lists.llvm.org> *On Behalf Of *Zhaoshi > Zheng via llvm-dev > *Sent:* Tuesday, July 14, 2020 21:34 > *To:* Mitch Phillips <mitchp at google.com> > *Cc:* llvm-dev at lists.llvm.org; Stephen Long <steplong at quicinc.com> > *Subject:* [EXT] Re: [llvm-dev] [MTE] Tagging Globals > > > > Thanks for the update, Phillips. > > > > Yes, please add me, Stephen and Ana (CCed) to Phabricator reviews. > > > > Zhaoshi > > > > *From:* Mitch Phillips <mitchp at google.com> > *Sent:* Tuesday, July 14, 2020 19:10 > *To:* Zhaoshi Zheng <zhaoshiz at quicinc.com> > *Cc:* llvm-dev at lists.llvm.org; Stephen Long <steplong at quicinc.com> > *Subject:* [EXT] Re: [llvm-dev] [MTE] Tagging Globals > > > > Hi Zhaoshi, > > > > Currently there's no global tagging instrumentation for MTE. We have a > good idea about the implementation's design - but no patches are ready to > be shared at this stage. > > > > If you'd like - I'd be more than happy to CC yourself and Stephen on any > Phabricator reviews :). > > > > On Tue, Jul 14, 2020 at 5:04 PM Zhaoshi Zheng via llvm-dev < > llvm-dev at lists.llvm.org> wrote: > > Hello, > > > > We’re evaluating memory tagging (MTE) on some internal workloads. > > > > We noticed that stack variables are tagged by an instrumentation pass and > heap objects are handled by the allocator (Scudo). > > > > How about global variables? We tried a simple case using > -march=armv8a+memtag -fsanitize=memtag, but found no tagging: > > > > Are we missing anything or tagging globals is still in progress? > > > > *int global_array[16];* > > > > *int main(int argc, char **argv) {* > > * global_array[1] = 0;* > > * return global_array[argc + 16]; // BOOM* > > *}* > > > > clang++ -O1 --target=aarch64-linux -march=armv8.5a+memtag > -fsanitize=memtag test.cpp -S -o test.s > > > > *main: // @main* > > *.Lmain$local:* > > *// %bb.0: // %entry* > > * adrp x8, global_array* > > * add x8, x8, :lo12:global_array* > > * str wzr, [x8, #4]* > > * add x8, x8, w0, sxtw #2* > > * ldr w0, [x8, #64]* > > * ret* > > *.Lfunc_end0:* > > * .size main, .Lfunc_end0-main* > > > > _______________________________________________ > LLVM Developers mailing list > llvm-dev at lists.llvm.org > https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev > >-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20200715/8ec3ca78/attachment.html>