diff mbox series

[v3,for-5.1] acpi-pm-tmr: allow small-size reads

Message ID 1594733782.723411.2142.nullmailer@msgid.tls.msk.ru
State New
Headers show
Series [v3,for-5.1] acpi-pm-tmr: allow small-size reads | expand

Commit Message

Michael Tokarev July 14, 2020, 1:27 p.m. UTC 
As found in LP#1886318, MacOS Catalina performs 2-byte reads
on the acpi timer address space while the spec says it should
be 4-byte. Allow any small reads.

Reported-By: Simon John <git@the-jedi.co.uk>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
BugLink: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=964247
BugLink: https://bugs.launchpad.net/bugs/1886318
Fixes: 77d58b1e47c8d1c661f98f12b47ab519d3561488 (apci: switch timer to memory api)
Fixes: 5d971f9e672507210e7 (memory: Revert "memory: accept mismatching sizes in memory_region_access_valid")
---
 hw/acpi/core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

v2: fixed bug#, use the right form of S-o-b, and allow up to 1 byte reads.
v3: added BugLink & Fixes references, updated comment

I'm applying this to debian qemu package, need the fix
faster in order to release security updates for other
branches.
diff mbox series

Patch

diff --git a/hw/acpi/core.c b/hw/acpi/core.c
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -530,7 +530,10 @@  static void acpi_pm_tmr_write(void *opaque, hwaddr addr, uint64_t val,
 static const MemoryRegionOps acpi_pm_tmr_ops = {
     .read = acpi_pm_tmr_read,
     .write = acpi_pm_tmr_write,
-    .valid.min_access_size = 4,
+    .impl.min_access_size = 4,
+     /* at least MacOS Catalina reads 2 bytes and fails if it doesn't work */
+     /* allow 1-byte reads too, memory API will do all the conversion needed */
+    .valid.min_access_size = 1,
     .valid.max_access_size = 4,
     .endianness = DEVICE_LITTLE_ENDIAN,
 };