Merge tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git...

Pull xen fixes from Juergen Gross:

 - fix build warning

 - avoid concurrent accesses to the Xen PV console ring page

* tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/PVH: avoid 32-bit build warning when obtaining VGA console info
  hvc/xen: prevent concurrent accesses to the shared ring

diff --git a/arch/x86/xen/enlighten_pvh.c b/arch/x86/xen/enlighten_pvh.c
index 1da44aca896c6029ecc4a0b4635d5b3eaa8d9f01..ada3868c02c231d0f10863cabf71a076f003acb5 100644 (file)
--- a/arch/x86/xen/enlighten_pvh.c
+++ b/arch/x86/xen/enlighten_pvh.c
@@ -48,7 +48,7 @@ void __init xen_pvh_init(struct boot_params *boot_params)
                struct xen_platform_op op = {
                        .cmd = XENPF_get_dom0_console,
                };
-               long ret = HYPERVISOR_platform_op(&op);
+               int ret = HYPERVISOR_platform_op(&op);
 
                if (ret > 0)
                        xen_init_vga(&op.u.dom0_console,

diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 5bddb2f5e93185eca993595dd0c44f7cc7d1ec46..98764e740c07830495dc5d3532e08d3b40a9ee7b 100644 (file)
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -43,6 +43,7 @@ struct xencons_info {
        int irq;
        int vtermno;
        grant_ref_t gntref;
+       spinlock_t ring_lock;
 };
 
 static LIST_HEAD(xenconsoles);
@@ -89,12 +90,15 @@ static int __write_console(struct xencons_info *xencons,
        XENCONS_RING_IDX cons, prod;
        struct xencons_interface *intf = xencons->intf;
        int sent = 0;
+       unsigned long flags;
 
+       spin_lock_irqsave(&xencons->ring_lock, flags);
        cons = intf->out_cons;
        prod = intf->out_prod;
        mb();                   /* update queue values before going on */
 
        if ((prod - cons) > sizeof(intf->out)) {
+               spin_unlock_irqrestore(&xencons->ring_lock, flags);
                pr_err_once("xencons: Illegal ring page indices");
                return -EINVAL;
        }
@@ -104,6 +108,7 @@ static int __write_console(struct xencons_info *xencons,
 
        wmb();                  /* write ring before updating pointer */
        intf->out_prod = prod;
+       spin_unlock_irqrestore(&xencons->ring_lock, flags);
 
        if (sent)
                notify_daemon(xencons);
@@ -146,16 +151,19 @@ static int domU_read_console(uint32_t vtermno, char *buf, int len)
        int recv = 0;
        struct xencons_info *xencons = vtermno_to_xencons(vtermno);
        unsigned int eoiflag = 0;
+       unsigned long flags;
 
        if (xencons == NULL)
                return -EINVAL;
        intf = xencons->intf;
 
+       spin_lock_irqsave(&xencons->ring_lock, flags);
        cons = intf->in_cons;
        prod = intf->in_prod;
        mb();                   /* get pointers before reading ring */
 
        if ((prod - cons) > sizeof(intf->in)) {
+               spin_unlock_irqrestore(&xencons->ring_lock, flags);
                pr_err_once("xencons: Illegal ring page indices");
                return -EINVAL;
        }
@@ -179,10 +187,13 @@ static int domU_read_console(uint32_t vtermno, char *buf, int len)
                xencons->out_cons = intf->out_cons;
                xencons->out_cons_same = 0;
        }
+       if (!recv && xencons->out_cons_same++ > 1) {
+               eoiflag = XEN_EOI_FLAG_SPURIOUS;
+       }
+       spin_unlock_irqrestore(&xencons->ring_lock, flags);
+
        if (recv) {
                notify_daemon(xencons);
-       } else if (xencons->out_cons_same++ > 1) {
-               eoiflag = XEN_EOI_FLAG_SPURIOUS;
        }
 
        xen_irq_lateeoi(xencons->irq, eoiflag);
@@ -239,6 +250,7 @@ static int xen_hvm_console_init(void)
                info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
                if (!info)
                        return -ENOMEM;
+               spin_lock_init(&info->ring_lock);
        } else if (info->intf != NULL) {
                /* already configured */
                return 0;
@@ -275,6 +287,7 @@ err:
 
 static int xencons_info_pv_init(struct xencons_info *info, int vtermno)
 {
+       spin_lock_init(&info->ring_lock);
        info->evtchn = xen_start_info->console.domU.evtchn;
        /* GFN == MFN for PV guest */
        info->intf = gfn_to_virt(xen_start_info->console.domU.mfn);
@@ -325,6 +338,7 @@ static int xen_initial_domain_console_init(void)
                info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
                if (!info)
                        return -ENOMEM;
+               spin_lock_init(&info->ring_lock);
        }
 
        info->irq = bind_virq_to_irq(VIRQ_CONSOLE, 0, false);
@@ -482,6 +496,7 @@ static int xencons_probe(struct xenbus_device *dev,
        info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;
+       spin_lock_init(&info->ring_lock);
        dev_set_drvdata(&dev->dev, info);
        info->xbdev = dev;
        info->vtermno = xenbus_devid_to_vtermno(devid);