<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> <style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style> </head> <body dir="ltr"> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> + <a id="OWAAM996403" class="J9Y1oNF3ZpoR5LC3M2PHm mention ms-bgc-nlr ms-fcl-b" href="mailto:Samer.El-Haj-Mahmoud@arm.com"> @Samer El-Haj-Mahmoud</a></div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> <br> </div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> Hello Leif/Ard/Sami/Samer,</div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> <br> </div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> Can you please look at this patch and provide some feedback?</div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> <br> </div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> Thanks</div> <div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);"> Ashish</div> <div id="appendonsend"></div> <hr style="display:inline-block;width:98%" tabindex="-1"> <div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Ashish Singhal <ashishsingha@nvidia.com><br> <b>Sent:</b> Monday, February 21, 2022 7:42 PM<br> <b>To:</b> devel@edk2.groups.io <devel@edk2.groups.io>; sami.mujawar@arm.com <sami.mujawar@arm.com>; ardb+tianocore@kernel.org <ardb+tianocore@kernel.org>; quic_llindhol@quicinc.com <quic_llindhol@quicinc.com><br> <b>Cc:</b> Ashish Singhal <ashishsingha@nvidia.com><br> <b>Subject:</b> [PATCH] ArmPkg: Invalidate Instruction Cache On MMU Enable</font> <div> </div> </div> <div class="BodyFragment"><font size="2"><span style="font-size:11pt;"> <div class="PlainText">Even with MMU turned off, instruction cache can speculate<br> and fetch instructions. This can cause a crash if region<br> being executed has been modified recently. With this patch,<br> we ensure that instruction cache is invalidated right after<br> MMU has been enabled and any potentially stale instruction<br> fetched earlier has been discarded.<br> <br> This is specially helpful when the memory attributes of a<br> region in MMU are being changed and some instructions<br> operating on the region are prefetched in the instruction<br> cache.<br> <br> Signed-off-by: Ashish Singhal <ashishsingha@nvidia.com><br> ---<br> ArmPkg/Library/ArmLib/AArch64/AArch64Support.S | 4 +++-<br> ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibReplaceEntry.S | 2 ++<br> 2 files changed, 5 insertions(+), 1 deletion(-)<br> <br> diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S<br> index d3cc1e8671..9648245182 100644<br> --- a/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S<br> +++ b/ArmPkg/Library/ArmLib/AArch64/AArch64Support.S<br> @@ -89,7 +89,9 @@ ASM_FUNC(ArmEnableMmu)<br> dsb nsh<br> isb<br> msr sctlr_el3, x0 // Write back<br> -4: isb<br> +4: ic iallu<br> + dsb sy<br> + isb<br> ret<br> <br> <br> diff --git a/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibReplaceEntry.S b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibReplaceEntry.S<br> index 66ebca571e..56cc2dd73f 100644<br> --- a/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibReplaceEntry.S<br> +++ b/ArmPkg/Library/ArmMmuLib/AArch64/ArmMmuLibReplaceEntry.S<br> @@ -37,6 +37,8 @@<br> <br> // re-enable the MMU<br> msr sctlr_el\el, x8<br> + ic iallu<br> + dsb sy<br> isb<br> .endm<br> <br> -- <br> 2.17.1<br> <br> </div> </span></font></div> </body> </html> <div width="1" style="color:white;clear:both">_._,_._,_</div> <hr> Groups.io Links:<p> You receive all messages sent to this group. <p> <a target="_blank" href="https://edk2.groups.io/g/devel/message/86881">View/Reply Online (#86881)</a> | | <a target="_blank" href="https://groups.io/mt/89309504/1813853">Mute This Topic</a> | <a href="https://edk2.groups.io/g/devel/post">New Topic</a><br> <a href="https://edk2.groups.io/g/devel/editsub/1813853">Your Subscription</a> | <a href="mailto:devel+owner@edk2.groups.io">Contact Group Owner</a> | <a href="https://edk2.groups.io/g/devel/unsub">Unsubscribe</a> [edk2-devel-archive@redhat.com]<br> <div width="1" style="color:white;clear:both">_._,_._,_</div>