Second reboot worked. I did some extensive disk writing (around 1GB), got the read-only problem, and dmesg says:


[  962.226687] sdhci: Timeout waiting for Buffer Read Ready interrupt during tuning procedure, falling back to fixed sampling clock
[  972.262988] mmc0: Timeout waiting for hardware interrupt.
[  972.264987] ------------[ cut here ]------------
[  972.265008] WARNING: CPU: 1 PID: 0 at /build/buildd/linux-3.13.0/drivers/mmc/host/sdhci.c:989 sdhci_send_command+0xc32/0xd60 [sdhci]()
[  972.265010] Modules linked in: uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core videodev rfcomm bnep nls_iso8859_1 hid_generic hp_wmi sparse_keymap arc4 intel_rapl coretemp rtl8723be kvm crct10dif_pclmul crc32_pclmul btcoexist rtl8723_common ghash_clmulni_intel cryptd i915_bdw usbhid rtl_pci hid snd_hda_codec_hdmi rtlwifi snd_hda_codec_realtek btusb mac80211 bluetooth serio_raw rtsx_pci_ms memstick cfg80211 wmi snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_page_alloc snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer snd intel_ips drm_kms_helper video hp_wireless drm i2c_algo_bit parport_pc soundcore joydev mac_hid ppdev lp parport usb_storage mmc_block rtsx_pci_sdmmc psmouse rtsx_pci sdhci_acpi sdhci
[  972.265057] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G        W     3.13.0-45-generic #74-Ubuntu
[  972.265060] Hardware name: Hewlett-Packard HP Stream Notebook PC 13/802A, BIOS F.05 11/28/2014
[  972.265062]  0000000000000009 ffff880076683d28 ffffffff81720eb6 0000000000000000
[  972.265066]  ffff880076683d60 ffffffff810677cd 0000000000000001 ffff880079947650
[  972.265070]  ffff88003f5e1930 ffff88003f5e1970 ffff8800799474c0 ffff880076683d70
[  972.265074] Call Trace:
[  972.265077]  <IRQ>  [<ffffffff81720eb6>] dump_stack+0x45/0x56
[  972.265089]  [<ffffffff810677cd>] warn_slowpath_common+0x7d/0xa0
[  972.265093]  [<ffffffff810678aa>] warn_slowpath_null+0x1a/0x20
[  972.265099]  [<ffffffffa0003aa2>] sdhci_send_command+0xc32/0xd60 [sdhci]
[  972.265105]  [<ffffffff813709aa>] ? delay_tsc+0x4a/0x80
[  972.265108]  [<ffffffff813708dc>] ? __const_udelay+0x2c/0x30
[  972.265115]  [<ffffffffa0001164>] ? sdhci_reset+0xa4/0x1b0 [sdhci]
[  972.265121]  [<ffffffffa00043e5>] sdhci_finish_data+0x115/0x3c0 [sdhci]
[  972.265128]  [<ffffffffa0004690>] ? sdhci_finish_data+0x3c0/0x3c0 [sdhci]
[  972.265134]  [<ffffffffa000470d>] sdhci_timeout_timer+0x7d/0xc0 [sdhci]
[  972.265138]  [<ffffffff81074386>] call_timer_fn+0x36/0x100
[  972.265145]  [<ffffffffa0004690>] ? sdhci_finish_data+0x3c0/0x3c0 [sdhci]
[  972.265148]  [<ffffffff8107531f>] run_timer_softirq+0x1ef/0x2f0
[  972.265153]  [<ffffffff8106cc1c>] __do_softirq+0xec/0x2c0
[  972.265157]  [<ffffffff8106d165>] irq_exit+0x105/0x110
[  972.265162]  [<ffffffff81733d55>] smp_apic_timer_interrupt+0x45/0x60
[  972.265166]  [<ffffffff817326dd>] apic_timer_interrupt+0x6d/0x80
[  972.265168]  <EOI>  [<ffffffff815d3712>] ? cpuidle_enter_state+0x52/0xc0
[  972.265175]  [<ffffffff815d3839>] cpuidle_idle_call+0xb9/0x1f0
[  972.265180]  [<ffffffff8101d35e>] arch_cpu_idle+0xe/0x30
[  972.265185]  [<ffffffff810bef35>] cpu_startup_entry+0xc5/0x290
[  972.265190]  [<ffffffff810413fd>] start_secondary+0x21d/0x2d0
[  972.265192] ---[ end trace fa59f6fabf0e6688 ]---
[  972.267360] mmcblk0: error -110 transferring data, sector 29645704, nr 224, cmd response 0x0, card status 0x0
[  972.267370] blk_update_request: 11 callbacks suppressed
[  972.267373] end_request: I/O error, dev mmcblk0, sector 29645704
[  972.267379] end_request: I/O error, dev mmcblk0, sector 29645712
[  972.267383] end_request: I/O error, dev mmcblk0, sector 29645720
[  972.267387] end_request: I/O error, dev mmcblk0, sector 29645728
[  972.267390] end_request: I/O error, dev mmcblk0, sector 29645736
[  972.267394] end_request: I/O error, dev mmcblk0, sector 29645744
[  972.267397] end_request: I/O error, dev mmcblk0, sector 29645752
[  972.267400] end_request: I/O error, dev mmcblk0, sector 29645760
[  972.267403] end_request: I/O error, dev mmcblk0, sector 29645768
[  972.267406] end_request: I/O error, dev mmcblk0, sector 29645776
[  972.267529] Aborting journal on device mmcblk0p5-8.
[  972.267544] EXT4-fs error (device mmcblk0p5) in ext4_reserve_inode_write:4902: Journal has aborted
[  972.268665] EXT4-fs error (device mmcblk0p5) in ext4_free_blocks:4882: Journal has aborted
[  972.269152] EXT4-fs error (device mmcblk0p5) in ext4_reserve_inode_write:4902: Journal has aborted
[  972.360668] EXT4-fs (mmcblk0p5): Remounting filesystem read-only
[  972.438561] EXT4-fs error (device mmcblk0p5): mpage_map_and_submit_extent:2273: comm http: Failed to mark inode 320098 dirty