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Blame 0203-cpu_physical_memory_write_rom-needs-to-do-TB-invalid.patch

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From 897815f54c446671cae0f202c54e9548e969d427 Mon Sep 17 00:00:00 2001
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From: David Gibson <david@gibson.dropbear.id.au>
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Date: Mon, 10 Sep 2012 12:30:57 +1000
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Subject: [PATCH] cpu_physical_memory_write_rom() needs to do TB invalidates
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cpu_physical_memory_write_rom(), despite the name, can also be used to
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write images into RAM - and will often be used that way if the machine
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uses load_image_targphys() into RAM addresses.
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However, cpu_physical_memory_write_rom(), unlike cpu_physical_memory_rw()
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doesn't invalidate any cached TBs which might be affected by the region
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written.
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This was breaking reset (under full emu) on the pseries machine - we loaded
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our firmware image into RAM, and while executing it rewrite the code at
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the entry point (correctly causing a TB invalidate/refresh).  When we
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reset the firmware image was reloaded, but the TB from the rewrite was
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still active and caused us to get an illegal instruction trap.
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This patch fixes the bug by duplicating the tb invalidate code from
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cpu_physical_memory_rw() in cpu_physical_memory_write_rom().
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Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
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(cherry picked from commit 0b57e287138728f72d88b06e69b970c5d745c44a)
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Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
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---
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 exec.c | 7 +++++++
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 1 file changed, 7 insertions(+)
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diff --git a/exec.c b/exec.c
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index ad175db..3fdbbde 100644
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--- a/exec.c
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+++ b/exec.c
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@@ -3521,6 +3521,13 @@ void cpu_physical_memory_write_rom(target_phys_addr_t addr,
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             /* ROM/RAM case */
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             ptr = qemu_get_ram_ptr(addr1);
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             memcpy(ptr, buf, l);
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+            if (!cpu_physical_memory_is_dirty(addr1)) {
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+                /* invalidate code */
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+                tb_invalidate_phys_page_range(addr1, addr1 + l, 0);
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+                /* set dirty bit */
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+                cpu_physical_memory_set_dirty_flags(
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+                    addr1, (0xff & ~CODE_DIRTY_FLAG));
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+            }
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             qemu_put_ram_ptr(ptr);
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         }
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         len -= l;
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-- 
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1.7.12.1
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