From 93de2a6a4b91b72607136dd656edf03fb399d27f Mon Sep 17 00:00:00 2001 From: Sean Christopherson Date: Wed, 23 Sep 2026 09:37:21 -0700 Subject: KVM: SEV: Do cache maintenance on the source VM during intra-host migration Manually perform cache maintenance on the source VM during intra-host migration to ensure no stale data is left in CPU caches after the VM is destroyed. Because the source VM is "converted" to a non-SEV VM, KVM's memory reclaim flows won't trigger cache maintenance, e.g. when all guest memory is reclaimed in response to detaching from the mmu_notifier. Note, relying on the destination VM to do cache maintenance isn't an option as KVM doesn't require identical guest memory configurations, i.e. the source VM may have access to memory that the destination VM does not. Enforcing equivalent memory configurations is infeasible, as it would require a *deep* comparison of memslots, e.g. to verify that not only are the memslot identical, but what the memslots point at is also identical. Fixes: b56639318bb2 ("KVM: SEV: Add support for SEV intra host migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Signed-off-by: Sean Christopherson Message-ID: <20260923163721.1584779-3-seanjc@google.com> Signed-off-by: Paolo Bonzini --- drivers/video/fbdev/sstfb.c | 1544 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1544 insertions(+) create mode 100644 drivers/video/fbdev/sstfb.c (limited to 'drivers/video/fbdev/sstfb.c') diff --git a/drivers/video/fbdev/sstfb.c b/drivers/video/fbdev/sstfb.c new file mode 100644 index 000000000..274555782 --- /dev/null +++ b/drivers/video/fbdev/sstfb.c @@ -0,0 +1,1544 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/drivers/video/sstfb.c -- voodoo graphics frame buffer + * + * Copyright (c) 2000-2002 Ghozlane Toumi + * + * Created 15 Jan 2000 by Ghozlane Toumi + * + * Contributions (and many thanks) : + * + * 03/2001 James Simmons + * 04/2001 Paul Mundt + * 05/2001 Urs Ganse + * (initial work on voodoo2 port, interlace) + * 09/2002 Helge Deller + * (enable driver on big-endian machines (hppa), ioctl fixes) + * 12/2002 Helge Deller + * (port driver to new frambuffer infrastructure) + * 01/2003 Helge Deller + * (initial work on fb hardware acceleration for voodoo2) + * 08/2006 Alan Cox + * Remove never finished and bogus 24/32bit support + * Clean up macro abuse + * Minor tidying for format. + * 12/2006 Helge Deller + * add /sys/class/graphics/fbX/vgapass sysfs-interface + * add module option "mode_option" to set initial screen mode + * use fbdev default videomode database + * remove debug functions from ioctl + */ + +/* + * The voodoo1 has the following memory mapped address space: + * 0x000000 - 0x3fffff : registers (4MB) + * 0x400000 - 0x7fffff : linear frame buffer (4MB) + * 0x800000 - 0xffffff : texture memory (8MB) + */ + +/* + * misc notes, TODOs, toASKs, and deep thoughts + +-TODO: at one time or another test that the mode is acceptable by the monitor +-ASK: Can I choose different ordering for the color bitfields (rgba argb ...) + which one should i use ? is there any preferred one ? It seems ARGB is + the one ... +-TODO: in set_var check the validity of timings (hsync vsync)... +-TODO: check and recheck the use of sst_wait_idle : we don't flush the fifo via + a nop command. so it's ok as long as the commands we pass don't go + through the fifo. warning: issuing a nop command seems to need pci_fifo +-FIXME: in case of failure in the init sequence, be sure we return to a safe + state. +- FIXME: Use accelerator for 2D scroll +-FIXME: 4MB boards have banked memory (FbiInit2 bits 1 & 20) + */ + +/* + * debug info + * SST_DEBUG : enable debugging + * SST_DEBUG_REG : debug registers + * 0 : no debug + * 1 : dac calls, [un]set_bits, FbiInit + * 2 : insane debug level (log every register read/write) + * SST_DEBUG_FUNC : functions + * 0 : no debug + * 1 : function call / debug ioctl + * 2 : variables + * 3 : flood . you don't want to do that. trust me. + * SST_DEBUG_VAR : debug display/var structs + * 0 : no debug + * 1 : dumps display, fb_var + * + * sstfb specific ioctls: + * toggle vga (0x46db) : toggle vga_pass_through + */ + +#undef SST_DEBUG + + +/* + * Includes + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include