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+Qemu 3.1 Aarch64 TLBI VAE1, x0
+
+Hello,
+
+In my code I'm trying to remove some permissions to a 4KiB MMU descriptor. After that I invalidate the MMU with 
+
+TLBI VAE1, x0
+
+where x0 is the start of the address of the 4 KiB page. 
+
+In Qemu 2.12 this did not work, but I worked around it with:
+
+
+    /* invalidate the address */
+    TLBI VAE1, x0
+
+
+    /*****************************************************************/
+    /*****************************************************************/
+    /* NOTE: THIS IS A TRICK FOR QEMU!!!!!!!!!!!!                                                               */
+    /* Apparently we have to change the TTBR0_EL1 when we change a descriptor (especially to remove permissions) */
+    /* Otherwise qemu (2.12) will continue with the same descriptor with permissions!                          **/
+   /*****************************************************************/
+   /*****************************************************************/
+     
+    /* do a trick (in qemu) */
+    mrs     x1 , TTBR0_EL1
+
+    ldr     x2 , =kernelTable0Table
+
+    msr     TTBR0_EL1 , x2
+
+    isb
+
+    msr     TTBR0_EL1 , x1
+
+    /* return from function */
+    ret
+
+
+That is, I just replaced the TTBR0_EL1 with a temporary value, and then restored it. (guess qemu 2.12 just needed to reload the values again).
+
+However, even this procedure is not working with qemu 3.1. (I just tested again with qemu 2.12 and the code works fine, with qemu 3.1 it does not).
+
+Thanks,
+Pharos team
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