similar to: [PATCH] virtio-console: avoid DMA from stack

On Wed, Feb 01, 2017 at 07:17:12PM +0530, Amit Shah wrote: > On (Wed) 01 Feb 2017 [00:02:27], Omar Sandoval wrote: > > From: Omar Sandoval <osandov at fb.com> > > > > put_chars() stuffs the buffer it gets into an sg, but that buffer may be > > on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it > > manifested as printks getting turned into NUL

On Wed, Feb 01, 2017 at 07:17:12PM +0530, Amit Shah wrote: > On (Wed) 01 Feb 2017 [00:02:27], Omar Sandoval wrote: > > From: Omar Sandoval <osandov at fb.com> > > > > put_chars() stuffs the buffer it gets into an sg, but that buffer may be > > on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it > > manifested as printks getting turned into NUL

From: Omar Sandoval <osandov at fb.com> If blk_mq_init_queue() returns an error, it gets assigned to vblk->disk->queue. Then, when we call put_disk(), we end up calling blk_put_queue() with the ERR_PTR, causing a bad dereference. Fix it by only assigning to vblk->disk->queue on success. Signed-off-by: Omar Sandoval <osandov at fb.com> --- drivers/block/virtio_blk.c | 3

From: Omar Sandoval <osandov at fb.com> If blk_mq_init_queue() returns an error, it gets assigned to vblk->disk->queue. Then, when we call put_disk(), we end up calling blk_put_queue() with the ERR_PTR, causing a bad dereference. Fix it by only assigning to vblk->disk->queue on success. Signed-off-by: Omar Sandoval <osandov at fb.com> --- drivers/block/virtio_blk.c | 3

On (Wed) 01 Feb 2017 [00:02:27], Omar Sandoval wrote: > From: Omar Sandoval <osandov at fb.com> > > put_chars() stuffs the buffer it gets into an sg, but that buffer may be > on the stack. This breaks with CONFIG_VMAP_STACK=y (for me, it > manifested as printks getting turned into NUL bytes). Seems reasonable. I wonder since all implementations of hvc do a memcpy, if we can

From: Francois Diakhate <fdiakh at gmail.com> Currently early_put_chars is not used by virtio_console because it can only be used once a port has been found, at which point it's too late because it is no longer needed. This patch should fix it. Acked-by: Christian Borntraeger <borntraeger at de.ibm.com> Signed-off-by: Amit Shah <amit.shah at redhat.com> Signed-off-by: Rusty

From: Francois Diakhate <fdiakh at gmail.com> Currently early_put_chars is not used by virtio_console because it can only be used once a port has been found, at which point it's too late because it is no longer needed. This patch should fix it. Acked-by: Christian Borntraeger <borntraeger at de.ibm.com> Signed-off-by: Amit Shah <amit.shah at redhat.com> Signed-off-by: Rusty

Fix the polling section of the hvc driver to use the global "last_hvc" variable, rather than the ttys. With this change debugging a xen dom0 kernel is possible via the following kernel parameter: kgdboc=hvc0 Signed-off-by: Ben Guthro <Benjamin.Guthro@citrix.com> diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c index 2d691eb..3750e74 100644 ---

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

On Mon, Jan 09, 2017 at 11:44:12AM -0800, Omar Sandoval wrote: > From: Omar Sandoval <osandov at fb.com> > > If blk_mq_init_queue() returns an error, it gets assigned to > vblk->disk->queue. Then, when we call put_disk(), we end up calling > blk_put_queue() with the ERR_PTR, causing a bad dereference. Fix it by > only assigning to vblk->disk->queue on success.

Hey Rusty, In this version: - Assume only one inbuf; no input buffering for ports - Remove the START/END delimiters for outgoing buffers - Remove the header that was sent along with each buffer - Remove unused buffers in the vqs at port remove time - Send a guest port open message to the host when a console port is attached - Remove cached buffers when ports are closed / disconnected - Send

Hey Rusty, In this version: - Assume only one inbuf; no input buffering for ports - Remove the START/END delimiters for outgoing buffers - Remove the header that was sent along with each buffer - Remove unused buffers in the vqs at port remove time - Send a guest port open message to the host when a console port is attached - Remove cached buffers when ports are closed / disconnected - Send

Hey Rusty, This is a respin of my patches on top of the series you posted. I've taken the liberty to modify your patches for style consistency and comments where needed, keeping the authorship info intact. I've had to update a few of your patches for functional changes, I've changed the authorship info on those patches. The (only) major functional change is to have a list for ports

Hey Rusty, This is a respin of my patches on top of the series you posted. I've taken the liberty to modify your patches for style consistency and comments where needed, keeping the authorship info intact. I've had to update a few of your patches for functional changes, I've changed the authorship info on those patches. The (only) major functional change is to have a list for ports

From: Rusty Russell <rusty@rustcorp.com.au> A simple console driver for lguest. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- drivers/char/Makefile | 1 drivers/char/hvc_lguest.c | 99 ++++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+) diff

From: Rusty Russell <rusty@rustcorp.com.au> A simple console driver for lguest. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- drivers/char/Makefile | 1 drivers/char/hvc_lguest.c | 99 ++++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+) diff

Expose multiple char devices ("ports") for simple communication between the host userspace and guest. Sample offline usages can be: poking around in a guest to find out the file systems used, applications installed, etc. Online usages can be sharing of clipboard data between the guest and the host, sending information about logged-in users to the host, locking the screen or session when

Expose multiple char devices ("ports") for simple communication between the host userspace and guest. Sample offline usages can be: poking around in a guest to find out the file systems used, applications installed, etc. Online usages can be sharing of clipboard data between the guest and the host, sending information about logged-in users to the host, locking the screen or session when

This patch set if my first attempt to make virtio_console usable on s390. To do so, I had to change hvc_console, because s390 has no request_irq and no free_irq. I want to get feedback from the main users of hvc_console before I proceed. The basic idea of this patch set is to remove the calls to request_irq and free_irq and replace them with backend specific callbacks. Please see the